This creamy casserole can be made a day ahead for toting to the cottage.
Prepare completely but do not bake. Cover and refrigerate up to 1 day. Then bake, uncovered, in preheated 375F (190C) oven until cheese is golden, about 40 minutes.
Oval-shaped plum tomatoes, which are fleshier and more flavourful than regular slicing varieties, contain, like all tomatoes, vitamins C and A, potassium and fibre. Cooked and canned tomatoes are also one of the best sources of lycopene, a red pigment which is believed to have antioxidant properties.