In a large bowl, whisk the dry ingredients: flour, baking powder, cinnamon, and salt
In a blender (I use a Ninja), blend the spinach, milk, banana, (cooled) melted butter, egg, and vanilla until all the spinach is blended completely
Straight from the blender, pour the spinach mixture over the dry ingredients and fold with a rubber spatula until everything is incorporated
Heat a cast iron or non-stick pan over medium-low heat, and melt butter into the pan
Pour about 1/4 cup of batter into the pan, adding as many 1/4 cup circles as will fit, and cook until little bubbles appear around the edges, then quickly flip
Cook each pancake until set about 1-2 minutes more
Transfer cooked pancakes to a cooling rack and continue making the batter
Use whipped cream, strawberries, bananas, and mini chocolate chips to make the Grinch's face (as shown in the pictures)