Makes 16 2 x 2-inch squares
2-tablespoons unsalted butter, melted
3 eggs, beaten
1-cup whole milk
1-cup All-Purpose flour
1-teaspoon kosher salt
1-teapsoon baking powder
4 cups (1-lb) cheddar cheese, grated
1/4-cup Parmesan cheese
1-lb chopped frozen spinach, thawed and drained
Preheat the oven to 375F. Line a 9 x 13-inch sheet tray with parchment and our over the melted butter to coat.
Beat eggs well in a mixing bowl and combine with salt, milk, flour, cheddar, spinach, and baking powder. Spread the batter evenly across the pan and sprinkle with Parmesan cheese.
Bake at 375°F for 30-40 minutes until the cheese has browned. Cool and cut into 2 x 2-inch squares.