Preheat oven to 325°F. Lightly grease a 9-inch pie or quiche pan.
Prepare spinach in microwave according to package directions. Let cool or run under cold water. Drain and squeeze out all liquid.
Meanwhile, in a small skillet, heat olive oil over medium heat and add red onion. Saute’ about 5 minutes; add green onions and garlic and cook another minute.
In a large bowl, combine beaten eggs, cottage cheese, cheddar cheese, onion mixture and spinach. Pour mixture into prepared pan and top with sliced tomatoes.
Bake, uncovered 45 minutes. Remove from oven and sprinkle with crushed croutons. Return to oven and bake an additional 15 minutes, or until eggs are set.
Let stand 15 minutes. Slice to serve.