Preheat oven to 190 degrees C. Cut bread slices in half diagonally, and arrange around edge of 23cm pie plate.
In a medium frypan, melt butter and saute zucchini until tender, about 3-5 minutes. Add tomato and oregano, and cook for 3 minutes. Stir in the flour, and spoon mixture into centre of the bread-lined pie plate.
In a bowl, mix the cottage cheese, eggs, yoghurt, and 1/2 the Parmesan cheese. Spoon this mixture over the vegetables in the pie plate, and sprinkle with remaining Parmesan cheese.
Bake 30 minutes in the preheated oven until firm in centre.