Begin by cooking the whole-grain macaroni or penne according to package instructions until al dente. Drain and set aside.
In a large skillet, heat a splash of oil over medium heat. Add the diced yellow onion and sauté until translucent, about 3-4 minutes. Add the ground turkey and cook until browned and cooked through, breaking it apart with a wooden spoon as it cooks.
Stir in the kosher salt, chili powder, cumin, and black pepper. Mix well to evenly coat the turkey with spices.
Pour the salsa into the skillet with the turkey mixture. Stir to combine and let it simmer for about 5 minutes to meld flavors.
In a large mixing bowl, combine the cooked pasta, turkey and salsa mixture, and chopped cilantro. Mix until evenly distributed.
Fold in the shredded Mexican-style cheese, reserving some for topping the casserole.
Preheat oven to 350°F (175°C). Transfer the pasta mixture into a greased baking dish. Sprinkle reserved cheese on top.
Bake for 25-30 minutes, until cheese is bubbly and slightly golden. Remove from oven and let cool for a few minutes.
Top with additional chopped cilantro for garnish. Serve warm and enjoy your Tex-Mex Meaty Mac n Cheese Casserole!