Preheat oven to 375° F. You'll need two 12-cup muffin pans, as this recipe makes 16 muffins. (You can also use a mini muffin tin to increase the number of muffins.) Add muffin liners to 16 muffin cups and set aside. In a large bowl whisk together dry ingredients: flour, brown sugar, baking soda, and salt.
2 cups flour, 1/2 cup brown sugar, 3 tsp baking soda, 1 tsp salt
Add spinach, milk, eggs, avocado, and butter to a food processor. Blend until well combined, about 5 minutes.
3 cups spinach, 2 eggs, 1 avocado, 2 tbsp butter, 1 cup milk
Pour the spinach mixture into the flour mix. Mix with a spatula until well combined. Gently combine the chocolate chips until evenly spread.
1/2 cup chocolate chips
Fold half of the chocolate chips into the mixture.
Pour the batter into cupcake liners leaving some room for expanding.
Decorate the muffins with chocolate chips and edible googly eyes.
1/2 cup chocolate chips, edible googly eyes
Bake for 18-22 minutes, until the tops are no longer soft. You can also check the doneness with a toothpick by inserting it all the way into one of the monster muffins. If it comes out dry, then muffins are ready. Let them cool. Enjoy!