Preheat oven to 350°F:
Preheat oven to 350°F (175°C). Grease or line a 12-cup muffin tin with cupcake liners.Blend wet ingredients:
In a high-powered blender, combine banana, zucchini, spinach, egg, milk, melted butter or coconut oil, and vanilla extract. Blend until smooth.Mix dry ingredients:
In a large mixing bowl, whisk together flour, sugar, cocoa powder, baking soda, and sea salt.Combine wet and dry:
Pour the blended mixture over the flour mixture and stir until just combined. Be careful not to overmix.Fold in chocolate chips:
Fold in 1/2 cup chocolate chips.Fill muffin cups:
Divide the batter evenly among the prepared muffin cups. Top with additional chocolate chips if desired.Bake muffins:
Bake for 23-26 minutes, until a toothpick inserted in the center comes out mostly clean with a few crumbs.Cool and enjoy:
Cool in the pan for 10 minutes, then transfer muffins to a wire rack to cool completely. Enjoy!