Fill a large Dutch oven halfway with water. Salt the water, and bring to a boil. When boiling stir in the pasta. Once the water comes back to a boil, add the frozen vegetables. Continue cooking until the pasta's cooked to al dente. Strain & set aside.
8-12 oz spiral pasta, 16 oz bag frozen peas & carrots, 1/2 cup frozen corn kernels
Add all of the milk EXCEPT for 1/3 cup to the Dutch oven. Bring the milk to a bubble, whisking often so it doesn't scorch. Add the remaining milk to a small bowl with the cornstarch, whisk together, and then whisk the mixture into the milk in the pot. Simmer just until slightly thickened.
1 quart 2 % milk, 2 tbsp cornstarch
Add the seasonings and cheese to the pot, stirring until the cheese has melted and the sauce is smooth. Let the sauce simmer until it's noticeably thicker. Remove the pot from heat.
1 1/2 tsp dried onion, 1/4 tsp garlic powder, 1/8 tsp smoked paprika, 1/4 tsp black pepper, seasoned salt, 3/4 cup shredded cheddar cheese
Add the tuna and cooked pasta mixture to the pot, tossing gently until evenly combined. Set aside.
1 7 oz can albacore tuna
In a small mixing bowl add both the crushed crackers and melted butter, stirring together until evenly combined. Spread this mixture evenly out over the pasta.
1 sleeve Ritz crackers, 2 1/2 tbsp butter
Bake the pasta at 350° for 12-15 minutes, then let it rest for 5 minutes.
Serve warm and enjoy!