Ingredients
Equipment
Method
Prep
- Preheat the oven to 350°F and line a 12-cup muffin tin with paper liners. This sets the temperature so the muffins bake immediately for a deeply cracked top.
Mix dry
- Whisk all-purpose flour, unsweetened cocoa powder, baking soda, baking powder, and salt in a large bowl until evenly combined. The mixture should look uniform with no cocoa streaks.
Mix wet
- Beat eggs, granulated sugar, vegetable oil, sour cream, and vanilla extract together until smooth. Stop when the batter looks glossy and fully combined.
Combine batter
- Stir the wet mixture into the dry mixture until just combined. Stop as soon as no dry flour remains to keep the crumb ultra-fudgy.
Add zucchini and chips
- Fold in the grated, squeezed-dry zucchini and ¾ cup of the semi-sweet chocolate chips. The batter will be thick and speckled, with zucchini distributed throughout.
Fill and top
- Divide the batter evenly among the muffin cups, filling them ¾ full, then top each with the remaining semi-sweet chocolate chips. Each cup should have visible chip pieces on the surface.
Bake
- Bake for 20–22 minutes at 350°F until a toothpick comes out with a few moist crumbs—do not overbake. Look for a deep, cracked top that springs back lightly when pressed.
Cool
- Cool the muffins in the pan for 5 minutes, then transfer to a wire rack. The centers will finish setting while the exterior stays tender and glossy.
Notes
Pro tip: squeeze the grated zucchini very dry (press in a clean towel) to prevent gummy pockets and help the chocolate pools stay molten. Store muffins in an airtight container at room temperature for up to 2 days or refrigerate for up to 5 days; rewarm 10–15 seconds for best texture. Freeze up to 2 months in a sealed bag and thaw overnight in the fridge. If you want a dairy-reduced option, use plain dairy-free sour cream in the same amount.