Southern Tomato Slab Pie

3 cups finely crushed buttery cracker crumbs (such as Ritz)
1 cup grated Parmesan cheese
1/2 cup butter, melted
3 pounds tomatoes, sliced into 1/4-inch thick rounds
1/2 teaspoon salt
1 cup mayonnaise
3/4 cup chopped scallions
1/2 teaspoon pepper
1 cup shredded cheddar cheese
1 cup shredded mozzarella cheese

1. Preheat the oven to 350 degrees.

2. Combine the cracker crumbs, Parmesan cheese and melted butter in a bowl.

3. Press the crust mixture into the bottom of a rectangular baking pan, pressing it up the sides a bit.

4. Place in the oven for 10 minutes or until crisp. Set aside to cool.

5. Lay out the tomato slices on a dish towel and season with salt.

6. Combine the mayonnaise, scallions, pepper and half of each of the cheeses in a bowl. Spread the mixture over the cooled crust.

7. Top with the tomatoes, and sprinkle the remaining cheese over the top.

8. Bake for 15 minutes or until the cheese is bubbly and slightly brown.