Press all the water out of the thawed spinach. Combine cottage cheese, cheddar cheese, spinach, eggs, oil, salt and pepper. Pour half of the mixture into a lightly greased 9 inch pie plate. Arrange tomato slices over spinach and cover with the remaining spinach mixture. Bake in a preheated 350° oven for 40 minutes or until a knife inserted in the center comes out clean.