In a bowl, combine the croutons and butter. Press onto the bottom of an ungreased 9-in. pie plate. In a bowl, combine the spinach, cottage cheese, Monterey Jack cheese, eggs, 1/4 cup Parmesan cheese, sour cream, onion and garlic salt. Spoon over crust. Bake at 350° for 35 minutes.
Garnish with tomato slices; sprinkle with remaining Parmesan cheese. Let stand for 5 minutes before slicing.