SourdoughVeganEasy

Vegan Sourdough Discard Black Bean and Sweet Potato Cakes

Name: Vegan Sourdough Discard Black Bean and Sweet Potato Cakes
Prep time: 20 min
Cook time: 20 min
Total time: 40 min
Yield: 4 servings
Cuisine: Vegan
Ingredients: 1 cup (240 ml) active sourdough discard (unfed or recently fed), at room temperature; 1 can (15 oz) (425 g) canned black beans, drained and rinsed; 8 oz (225 g) sweet potato, peeled, cut into ½-inch (1.25 cm) cubes, roasted or boiled until tender and cooled; ½ cup (85 g) cornmeal (polenta); ¼ cup (30 g) all-purpose flour; 1½ tsp (3¾ g) ground cumin; ½ tsp (1½ g) garlic powder; 1 tbsp (15 ml) fresh lime juice; ¾ tsp (4½ g) fine sea salt; ¼ tsp (½ g) freshly ground black pepper; 3 tbsp (45 ml) neutral oil (avocado, grapeseed, or vegetable oil)

From the MyKitchenBank Kitchen

Crispy-edged pan-fried patties that blend earthy black beans and roasted sweet potato with active sourdough discard, cumin, and a hint of lime. These cakes are hearty enough for a main course, tender inside with a golden crust, and work beautifully with avocado, cilantro, or a cooling vegan crema.

Prep: 20 min
Cook: 20 min
Wait: 15 min
Total: 55 min
Makes: 8 cakes (2 per serving)

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Steps

Before you start

Have your sourdough discard at room temperature (freshly fed or unfed)
Cut the sweet potato into ½-inch cubes so it roasts evenly
Preheat your oven to 425°F (220°C) if roasting fresh sweet potato
Drain and rinse canned black beans thoroughly to remove excess sodium and starch

1
Roast sweet potatoOven 425°F / 220°C
- Preheat your oven to 425°F (220°C).
- Toss the peeled, diced sweet potato cubes with 1 tbsp (15 ml) of oil and a small pinch of salt.
- Spread on a baking sheet and roast for 15–18 minutes, stirring halfway, until golden and fork-tender.
- Cool completely before mashing—this prevents heat from making the batter too wet.
- (If using pre-cooked sweet potato from another meal, ensure it is cool and well-drained.)
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Ready when: Sweet potato is golden, fork-tender, and no longer steaming
Tip: Do not skip cooling; hot potato will make the batter soupy and the cakes won't hold together.
2
Mash beans and potato
- In a medium bowl, combine the cooled sweet potato and drained black beans.
- Using a fork, mash them together until about half of the beans are broken (some texture is good).
- Aim for a chunky paste—you want flecks of bean and potato throughout, not a smooth puree.
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Ready when: Mixture is chunky and holds together loosely when squeezed
Tip: Partial mashing keeps the cakes from becoming dense; over-processing makes them heavy.
3
Fold in sourdough and dry ingredients
- Add the room-temperature sourdough discard, cornmeal, flour, cumin, garlic powder, lime juice, salt, and black pepper to the bean mixture.
- Gently fold with a spatula until just combined—do not overmix or the gluten will develop and toughen the cakes.
- The batter should be thick and hold a shape but still slightly sticky.
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Ready when: No streaks of flour visible; sourdough is fully incorporated
Tip: Mix gently and just until combined; overmixing creates tough, dense cakes.
4
Chill batter briefly
- Cover the bowl with a lid or plastic wrap and refrigerate for 15 minutes.
- This rests the dough, allows the cornmeal to fully hydrate, and makes the batter much easier to shape into firm cakes.
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Tip: Don't skip this step; a cold batter holds its shape much better when pan-fried.
5
Shape the cakes
- Working with damp hands (so the batter doesn't stick), scoop 3 tbsp (45 ml) of batter per cake and gently press into a patty about ¾ inch (2 cm) thick on a parchment-lined tray or plate.
- You should have 8 cakes total.
- Wet your hands between each one to prevent sticking.
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Ready when: 8 even patties, each about ¾ inch thick, resting on parchment
Tip: Keep your hands damp and work gently; these cakes are delicate until they hit the pan.
6
Heat the skillet and oil
- Place a large skillet or griddle (10–12 inches / 25–30 cm) over medium-high heat.
- Add the remaining 2 tbsp (30 ml) of oil and let it heat until shimmering, 1–2 minutes.
- A small piece of batter dropped in should sizzle immediately.
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Ready when: Oil is shimmering and moves freely in the pan
Tip: If oil smokes, the heat is too high and will burn the exterior before the inside cooks through.
7
Pan-fry the cakes (first side)
- Carefully transfer 4 cakes to the hot skillet, spacing them about ½ inch (1.25 cm) apart (don't crowd).
- Fry undisturbed for 4–5 minutes until the bottom is golden-brown and the edges look set.
- The cakes should feel firm enough to flip.
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Ready when: Bottom is golden-brown, edges are firm and pulling away slightly from the pan
Tip: Resist the urge to flip early; a well-set crust helps hold the cake together when flipped.
8
Pan-fry the cakes (second side)
- Using a thin spatula, gently slide under each cake and flip it over.
- Fry the second side for 3–4 minutes until golden-brown and the cake is cooked through.
- The exterior should be crispy and the interior tender.
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Ready when: Both sides are golden-brown; cake feels firm when gently pressed
Tip: Use a thin, sharp spatula to avoid breaking the delicate cakes during the flip.
9
Cook remaining cakes
- Transfer the cooked cakes to a paper-towel-lined plate to drain excess oil.
- Repeat steps 6–7 with the remaining 4 cakes, adjusting heat if needed.
- You may need to add a little more oil between batches.
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Ready when: All 8 cakes are golden-brown and cooked through
Tip: Keep finished cakes warm on a plate in a 200°F (95°C) oven while you finish the batch.
10
Serve hot
- Serve the warm cakes immediately with your choice of toppings: sliced avocado, fresh cilantro, lime wedges, diced red onion, salsa, or a cooling vegan crema (blended cashew cream with lime and garlic).
- They are best eaten fresh and warm.
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Tip: Set out toppings before cooking so you can plate and serve immediately while the cakes are still warm and crispy.

Good to know

Tips

Sourdough discard is forgiving—use it straight from the jar or 4–8 hours after feeding; both work beautifully here.
Roast or boil sweet potato ahead of time and cool completely; this reduces total active prep time significantly.
For extra crispy edges, pan-fry the cakes over medium-high heat (not medium) and resist moving them around.
Serve with a simple vegan crema: blend ¼ cup (60 ml) soaked cashews, ¼ cup (60 ml) water, 1 tbsp (15 ml) lime juice, 1 small garlic clove, and salt until smooth and creamy.

Make ahead

Batter can be made up to 12 hours ahead, covered, and refrigerated. Shape the cakes just before cooking for best results. Cooked cakes can be cooled and frozen in an airtight container for up to 3 months; reheat in a skillet over medium heat for 2–3 minutes per side.

Storage & reheating

Room temperature (1–2 hours): store in an airtight container. Refrigerator (3–4 days): cover and reheat in a skillet over medium heat for 2–3 minutes per side, or in a 375°F (190°C) oven for 8–10 minutes. Freezer (up to 3 months): layer cooked cakes with parchment, wrap well, and thaw in the fridge before reheating.

Substitutions

sweet potato → regular white or yellow potato (8 oz / 225 g), roasted or boiled until tender. The result will be less sweet and earthier; use an extra ½ tsp (1.25 g) of cumin to enhance warmth.
canned black beans → pinto beans, kidney beans, or chickpeas (1 can, 15 oz / 425 g, drained and rinsed). Any bean works; cumin pairs well with all of them. Avoid mashing too much if using chickpeas, as they have a firmer texture.
cornmeal (polenta) → additional all-purpose flour (½ cup / 60 g total flour instead of cornmeal). The cakes will be slightly denser and less crispy on the outside without cornmeal's grittiness. Reduce active ingredients by ¼ cup (60 ml) to avoid a wet batter.
fresh lime juice → fresh lemon juice or a small splash of apple cider vinegar. Both add brightness; lemon is sharper, vinegar is milder. Use the same amount.