Preheat oven to 350 degrees F. Lightly spray a 9-inch square baking pan with non-stick cooking spray.
In a large bowl, mix together the cottage cheese, eggs, egg whites, and green onions until well combined. Mix in cheddar cheese, melted butter, flour, salt, garlic, black pepper, and red pepper flakes until thoroughly mixed. Fold in the drained spinach.
Pour cheese/spinach mixture into the prepared baking pan. Sprinkle the top with the Parmesan cheese.
Bake approximately 45 to 55 minutes or until the top is golden. Remove from oven and let cool to room temperature. Cut into small squares.
Serve either at room temperature or warm.
This appetizer can be made ahead of time, refrigerated or frozen, and reheated in oven before serving.
Makes 30 small squares for appetizers or 6 large squares for brunch.
Spinach Cheese Squares Recipe: https://whatscookingamerica.net/appetizers/spinachcheesesquares.htm