Sweet Potato Katsu Curry is a delicious plant-based spin on the beloved Japanese katsu curry. This vegan Japanese curry features crispy, panko-crusted sweet potato cutlets served with a rich, savory curry sauce and fluffy steamed rice. Made with store-bought Japanese curry roux like S&B Golden Curry, it’s an easy recipe to recreate at home.
Instead of traditional meat-based katsu, this vegetable katsu curry uses roasted sweet potato for a tender, naturally sweet interior that contrasts perfectly with the crunchy coating. It’s a great recipe for anyone looking to try vegan Japanese food or mix up their weeknight dinners with something filling and satisfying. Serve with a side of miso soup and fluffy white Japanese rice. If you don't have a rice cooker, follow my step-by-step instructions for perfect Japanese rice without a rice cooker.
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Ingredients
Serves 4 | Prep time 15 mins | Cooking time 45 mins
For the curry
- 90g of S&B curry block (or equivalent)
- 650-700ml water
- 1 medium onion (150g)
- 1 medium carrot (100g)
- 5 baby potatoes or white potatoes (~180g)
- ½ medium red bell pepper (100g)
- 2 tablespoon neutral oil (1 for roasting and 1 for stir-frying)
For the katsu
- 5-6 medium sweet potatoes (~600g)
- 1 cup panko breadcrumbs
- ½ cup plain flour
- 200ml oat milk
- Neutral oil (for deep frying)
For serving
- 800g cooked Japanese rice
- 2 thinly sliced green onions (spring onions)
- Small bunch of cilantro (coriander), optional
Instructions
1. Preheat the oven to 180°C / 356° F, with the fan on. Then wash, peel and slice your sweet potato lengthways into 1cm thick oval discs.
2. Arrange the sweet potato slices in a single layer in a roasting tray. Drizzle with oil and toss to coat evenly, then roast for about 20 minutes until tender. Flip them halfway through to ensure even cooking and check for doneness by piercing with a fork - they should be soft but not falling apart.
3. Once the sweet potato slices are cooked, transfer them to a plate lined with kitchen paper. Let them cool and allow any excess oil to drain off for a crispier finish.
4. Peel your onion and chop it into small cubes, about 1cm in size - try to keep them even so they cook evenly as well.
5. Peel the garlic cloves and slice them thinly so they’ll melt into the curry as it simmers.
6. Peel your carrot, then cut it lengthwise into quarters. Slice each quarter into small cubes - this helps it cook faster and blend into the sauce.
7. Slice the pepper into rough 1-inch squares. They’ll hold their shape a bit in the curry and add sweetness and colour.
8. Give your potatoes a good scrub, then peel and cut into 1-inch cubes. Try to keep them uniform so they soften at the same rate.
9. Slice your spring onions finely - you’ll use these later as a fresh garnish to finish the dish.
10. Roughly chop a handful of cilantro leaves (coriander) for extra flavour and a bright, fresh finish at the end. Set aside.
11. Heat 1 tablespoon of oil in a large saucepan over medium heat. Add the chopped onions along with a pinch of salt - this helps draw out moisture and gets them sweating. Stir regularly until they soften and just start to turn golden.
12. Once your onions are starting to brown, add the rest of the chopped vegetables - garlic, carrot, pepper, and potatoes - along with another pinch of salt and a splash of soy sauce. Give everything a good stir and sauté for 3–4 minutes so the flavours start to come together.
13. Pour in your water, just enough to cover the vegetables, and bring it all to a gentle simmer. Let it bubble away for about 15–20 minutes, or until the potatoes are fork-tender and the veggies are cooked through.
14. When the potatoes are soft, stir in the Japanese curry stock cubes. Keep stirring as they melt into the liquid, and continue cooking until the sauce thickens. Once it’s done, pop the lid on and leave it on the lowest heat to keep warm.
15. Now get your katsu breading station ready. You’ll need three shallow bowls - one with plain flour, one with plant-based milk, and the last with panko breadcrumbs. Line them up in this order to make the dipping easy.
16. Take your cooled sweet potato slices and coat each one first in flour, then dip in the milk, then repeat those two steps for a double coating. This gives the panko a better surface to cling to and helps the crust hold up when frying.
17. Finally, press each double-dipped sweet potato slice into the panko crumbs, turning and pressing gently to make sure they’re completely coated. You want an even, generous layer of panko on all sides before frying.
18. Heat about 3cm of oil in a pan over medium heat. You’re aiming for a temperature of around 180°C. If you don’t have a thermometer, drop a small pinch of panko into the oil - once hot enough, it will sizzle and float to the top in 1 second.
19. Fry the breaded sweet potato slices in hot oil for 2–3 minutes on each side, working in batches to avoid overcrowding. Turn gently to keep the panko coating intact. Once golden and crispy, transfer to a paper-lined plate to drain and rest before plating.
20. To serve, start with a generous scoop of steamed Japanese rice on each plate. Spoon over the warm curry sauce, letting it pool around the rice.
21. Then gently lay your sweet potato katsu pieces on top. Finish with a sprinkle of sliced spring onions and chopped cilantro (coriander) for a fresh contrast - then dig in.
Hint: Shallow fry the sweet potato in small batches to keep the oil temperature consistent. If you crowd the pan with too many pieces at a time, the oil will cool down and your katsu can end up soggy instead of crispy. Give each piece space to fry properly to get that perfect golden crunch.
Substitutions
- Sweet Potato: Roasted eggplants or tofu slices make a great substitute.
- Panko: Gluten-free breadcrumbs for a GF version. or make your own breadcrumbs from toasted bread.
Variations
- Spicy: Add a pinch of chili flakes or some finely chopped fresh chili to the curry sauce for extra heat. A drizzle of La-yu (Japanese chili oil) on top also works brilliantly.
- More veg: Throw in extras like green beans, courgette, spinach, or mushrooms to bulk up the curry and use up what’s in your fridge.
- Lighter option: For a lower-fat version, cook the sweet potato katsu in an air fryer instead of deep frying - it still crisps up beautifully.
Equipment
You don’t need any fancy equipment for this recipe - just some basics. Grab a baking tray for roasting your sweet potato, a large saucepan for the curry, and a deep frying pan for the katsu (or an air fryer if you're using that instead). You’ll also need a few bowls to set up your breading station. That’s it!
Storage
For best results, always store the curry sauce and sweet potato katsu separately - combining them will make the katsu soggy.
Curry: The sauce keeps well in the fridge for up to 3 days and tastes even better the next day. Reheat on the stove or in the microwave until piping hot, stirring occasionally for even heating.
Sweet potato katsu: These are best enjoyed fresh, but you can store leftover cutlets in the fridge for up to 2 days. To bring back the crispiness, reheat them in a hot oven rather than the microwave.
Top Tip
Wait until your vegetables are fully cooked before adding the curry roux. If you add it too early or while the pot is too hot, it can stick to the bottom and burn, which affects both the flavour and texture of your curry. Stir continuously once added to help it dissolve evenly.
FAQ
In Japanese cooking, sweet potatoes are often roasted, simmered in soy-based broths, or used in tempura. For katsu-style dishes, they’re sliced, coated in panko breadcrumbs, and shallow- or deep-fried until golden and crispy. Roasting before breading helps bring out their natural sweetness and gives them a soft, fluffy center.
Great plant-based substitutes include sweet potato, tofu, aubergine (eggplant), or seitan. Sweet potato is especially popular for its creamy texture and slight sweetness, which pairs beautifully with the savory curry sauce and crispy coating in a katsu curry.
“Sweet potato panko” usually refers to sweet potato coated in panko breadcrumbs. To make it, roast or steam your sweet potato slices first, then double-dip in flour and plant-based milk before coating thoroughly in panko. Fry or bake until golden and crisp. For more detailed instructions, follow the step-by-step recipe on this page!
Japanese sweet potato is called satsumaimo (さつまいも). It has purple skin and a dense, sweet yellow flesh. It’s commonly used in both sweet and savory dishes across Japan. In this recipe, we use the more widely available orange-fleshed sweet potatoes, which are softer and slightly less starchy but still work perfectly for katsu.
Yes, absolutely! Sweet potato makes an excellent katsu base. Its soft, sweet interior contrasts perfectly with the crunchy panko crust and pairs well with Japanese curry sauce for a balanced and satisfying dish.
Related
Looking for more tasty vegan Japanese recipes? Try these:
Pairing
Some side dishes to serve with sweet potato katsu curry:
Sweet Potato Katsu Curry
Ingredients
For the curry
- 90 g of S&B curry block or equivalent
- 650-700 ml water
- 1 medium onion ~150g
- 1 medium carrot ~100g
- 5 baby potatoes or white potatoes ~180g
- ½ medium red bell pepper ~100g
- 2 tablespoon neutral oil (1 for roasting and 1 for stir-frying)
For the katsu
- 5-6 medium sweet potatoes ~600g
- 1 cup panko breadcrumbs
- ½ cup plain flour
- 200 ml oat milk
- Neutral oil (for deep frying)
For serving
- 800 g cooked Japanese rice
- 2 thinly sliced green onions (spring onions)
- Small bunch of cilantro (coriander) optional
Instructions
- Preheat the oven to 180°C / 356° F, with the fan on. Then wash, peel and slice your sweet potato lengthways into 1cm thick oval discs.
- Arrange the sweet potato slices in a single layer in a roasting tray. Drizzle with oil and toss to coat evenly, then roast for about 20 minutes until tender. Flip them halfway through to ensure even cooking and check for doneness by piercing with a fork - they should be soft but not falling apart.
- Once the sweet potato slices are cooked, transfer them to a plate lined with kitchen paper. Let them cool and allow any excess oil to drain off for a crispier finish.
- Peel your onion and chop it into small cubes, about 1cm in size - try to keep them even so they cook evenly as well.
- Peel the garlic cloves and slice them thinly so they’ll melt into the curry as it simmers.
- Peel your carrot, then cut it lengthwise into quarters. Slice each quarter into small cubes - this helps it cook faster and blend into the sauce.
- Slice the pepper into rough 1-inch squares. They’ll hold their shape a bit in the curry and add sweetness and colour.
- Give your potatoes a good scrub, then peel and cut into 1-inch cubes. Try to keep them uniform so they soften at the same rate.
- Slice your spring onions finely - you’ll use these later as a fresh garnish to finish the dish.
- Roughly chop a handful of cilantro leaves (coriander) for extra flavour and a bright, fresh finish at the end. Set aside.
- Heat 1 tablespoon of oil in a large saucepan over medium heat. Add the chopped onions along with a pinch of salt - this helps draw out moisture and gets them sweating. Stir regularly until they soften and just start to turn golden.
- Once your onions are starting to brown, add the rest of the chopped vegetables - garlic, carrot, pepper, and potatoes - along with another pinch of salt and a splash of soy sauce. Give everything a good stir and sauté for 3–4 minutes so the flavours start to come together.
- Pour in your water, just enough to cover the vegetables, and bring it all to a gentle simmer. Let it bubble away for about 15–20 minutes, or until the potatoes are fork-tender and the veggies are cooked through.
- When the potatoes are soft, stir in the Japanese curry stock cubes. Keep stirring as they melt into the liquid, and continue cooking until the sauce thickens. Once it’s done, pop the lid on and leave it on the lowest heat to keep warm.
- Now get your katsu breading station ready. You’ll need three shallow bowls - one with plain flour, one with plant-based milk, and the last with panko breadcrumbs. Line them up in this order to make the dipping easy.
- Take your cooled sweet potato slices and coat each one first in flour, then dip in the milk, then repeat those two steps for a double coating. This gives the panko a better surface to cling to and helps the crust hold up when frying.
- Finally, press each double-dipped sweet potato slice into the panko crumbs, turning and pressing gently to make sure they’re completely coated. You want an even, generous layer of panko on all sides before frying.
- Heat about 3cm of oil in a pan over medium heat. You’re aiming for a temperature of around 180°C. If you don’t have a thermometer, drop a small pinch of panko into the oil - once hot enough, it will sizzle and float to the top in 1 second.
- Fry the breaded sweet potato slices in hot oil for 2–3 minutes on each side, working in batches to avoid overcrowding. Turn gently to keep the panko coating intact. Once golden and crispy, transfer to a paper-lined plate to drain and rest before plating.
- To serve, start with a generous scoop of steamed Japanese rice on each plate. Spoon over the warm curry sauce, letting it pool around the rice.
- Then gently lay your sweet potato katsu pieces on top. Finish with a sprinkle of sliced spring onions and chopped cilantro (coriander) for a fresh contrast - then dig in.
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