Drain the tuna cans. Divide the fish into small pieces.
Boil the noodles according to package directions. Throw in a colander and rinse with hot water.
Toss noodles with tuna, celery, and green onions.
Add sour cream, mustard, mayonnaise, thyme, and salt.
Place half of the mixture in a greased bowl. Then, half the sliced zucchini. The next layer is the second half of the tuna mixture, and on top is the zucchini again Sprinkle with cheese.
Bake in the oven at 175 degrees for 30 minutes Sprinkle with tomato slices and serve.