Preheat oven to 350 degrees. In a large bowl, stir together butter, sugar, salt, and egg until combined. Add vanilla, zucchini, and sour cream and stir until incorporated. Sift flour and cocoa powder into bowl and stir until combined. Stir in chocolate.
Spray two mini muffin pans with cooking spray. Fill each cup with 2 tablespoons batter and top with a walnut. Bake until a toothpick inserted in center of a muffin comes out clean, 15 to 17 minutes. Let muffins cool slightly in pans on wire racks before serving.
This is a go to dessert for me since I first served them at a BBQ this past summer. Baking them right now for a dinner party.
These are incredible! I made a few substitutions to make them a tiny bit healthier- I used 1/2 whole wheat pastry flour and non-fat Greek yogurt in place of sour cream, and they were delicious. Great chocolatey flavor, quick and easy to make, a big hit!
These are super moist and delicious! Deep chocolate flavor!