1. 1. Preheat the oven to 375°F (190°C).

2. 2. Cook the macaroni according to package instructions, then drain and set aside.

3. 3. In a skillet, cook the boneless chicken breast until fully cooked. Season with salt and pepper, then dice into small pieces.

4. 4. In a large mixing bowl, combine the cooked macaroni, diced chicken, canned chopped tomatoes, drained corn, and shredded cheddar cheese. Mix well.

5. 5. Transfer the mixture into a casserole dish.

6. 6. Crush the Ritz crackers and sprinkle them over the top of the casserole.

7. 7. Bake in the preheated oven for 25-30 minutes or until the cheese is melted and bubbly.

8. 8. Serve hot and enjoy!