Drain the tomatoes in a collander, throw them in a pot with the other veggies, and cook 5 minutes or until soft. Drain and rinse the beans in the collander. Add beans and seasoning to pot. Cook 2 minutes.
Put two shells in the bottom of a 9x13 baking pan. Add 1/3 of your veggies in there with a slotted spoon. Add 1/3 of the cheese. Add more shells and repeat, finishing with a layer of shells on top. Tuck the edges of the shells down into the sides of the dish (so they don't burn).
Bake at 400F for about 30 minutes.