This post contains affiliate links.
My black bean chocolate mug cake is rich, fudgy, and ready in under ten minutes, all in a single mug in the microwave. No flour, no oven, no waiting!
save this recipe!If you’ve made my fudgy black bean brownies, you already know what black beans do in a chocolate batter. They disappear completely behind the cocoa, brown sugar, and chocolate chips, adding structure and a slightly fudgy density that flour simply can’t replicate in a mug cake.
The result is less spongy than a typical mug cake and more truffle-like, which is exactly what you want at 10pm when the sweet tooth hits.
The flax egg is the detail that makes this work without any regular eggs. Two minutes of sitting and it gels into a binder that holds the whole thing together through the microwave.
The testing
Mashing vs. blending the beans
Blending the beans produces a smoother batter but dirties extra equipment for a single-serving dessert. Mashing with a fork directly in the mug until mostly smooth, with a few small bits remaining, produces the same fudgy texture without the extra cleanup.
Cornstarch for texture
Optional but worth including if you want a slightly more cake-like result rather than a pure fudge texture. Without it the mug cake is denser and more brownie-like. Both are good; it comes down to what you’re craving.
Cook time matters more than mug size
Testing confirmed that the mug size doesn’t significantly change the cook time. What does matter is how you plan to eat it. Four and a half minutes produces the best texture for eating immediately. Four minutes is better if you’re storing it for later since it continues to firm up as it cools and can get slightly dry over time.
Key ingredients
- Black beans: About a third of a can, drained and rinsed. Mash directly in the mug until mostly smooth. They replace flour entirely and add the fudgy, dense texture that makes this better than a standard mug cake.
- Flax egg: Ground flaxseed mixed with water and left to sit for a few minutes. It gels into a binder that holds the batter together through the microwave.
- Cocoa powder: The backbone of the chocolate flavor.
- Yogurt or sour cream: Keeps the crumb moist rather than rubbery, which is the texture problem most microwave mug cakes have. Greek yogurt is slightly lighter; sour cream produces a richer result.
- Chocolate chips: Folded in last and melted into pockets during cooking. They’re what make this feel like a real dessert rather than a health food project.
If the black bean baking concept has you curious, my fudgy black bean brownies and fudgy chocolate black bean muffins are the full-batch versions worth making when you’re feeding more than one.
Black Bean Chocolate Mug Cake
Ingredients
- 1 tsp ground flax seed
- 2 tsp water
- ⅓ cup black beans, drained and rinsed, 57 g
- 2 Tbsp brown sugar, 40 g
- 1 Tbsp cocoa powder, 7 g
- 1 Tbsp oil or melted butter, 12 g
- 1 Tbsp yogurt or sour cream, 18 g
- 1 Tbsp milk, 15 mL
- ¼ tsp cornstarch, optional for more cake-like texture
- ¼ tsp baking powder
- 1 pinch of salt
- 2 Tbsp chocolate chips, 25 g
Instructions
- Flax Egg: In a microwave-safe mug, combine 1 tsp ground flax seed and 2 tsp water. Stir and let sit for 2 to 3 minutes to thicken.
- Mash Beans: Add ⅓ cup black beans (drained) directly to the mug and mash with a fork until mostly smooth. Some small bits are fine.
- Mix Batter: Add 2 Tbsp brown sugar, 1 Tbsp cocoa powder, 1 Tbsp oil or melted butter, 1 Tbsp yogurt or sour cream, 1 Tbsp milk, ¼ tsp cornstarch, ¼ tsp baking powder, and 1 pinch of salt. Stir until fully combined and smooth.
- Add Chocolate Chips: Fold in 2 Tbsp chocolate chips.
- Microwave: Microwave on 100% power for about 4 to 4½ minutes, until set in the center (a toothpick inserted should come out mostly clean with a few moist crumbs).
- Serve: Let sit for a few minutes before eating. The cake will continue to set as it cools.
Notes
Nutrition
Nutrition information calculated by Sarah Bond, degreed nutritionist.
did you make this?Leave a comment below and tag @liveeatlearn on social media! I love seeing what you’ve made!
