01 -
Preheat oven to 350°F (175°C).
02 -
Combine milk, bananas and spinach in a high-powered blender and blend until mostly smooth. A few lumps is acceptable. Transfer the mixture to a large mixing bowl.
03 -
Add egg and stir to lightly whisk. Incorporate sugar, vanilla, oil and Greek yogurt, stirring until well combined.
04 -
In a separate bowl, whisk together flour, baking soda, sea salt and cocoa powder until evenly distributed.
05 -
Gradually fold the dry ingredients into the wet ingredients until just combined. Stir in the chocolate chips, reserving some for topping if desired.
06 -
Line a 12-cup muffin pan with liners and divide the batter evenly. Sprinkle additional chocolate chips on top of each muffin if desired.
07 -
Bake for 18-22 minutes, or until a toothpick inserted into the center comes out clean.
08 -
Allow muffins to cool in the pan for several minutes before transferring to a wire rack.