Cook the pasta until al dente according to package instructions, then drain and set aside.
In a large skillet over medium heat, brown the ground beef or turkey until fully cooked. Drain any excess fat.
Add the diced onion and bell peppers to the skillet, cooking until softened, about 5 minutes.
Stir in the taco seasoning, diced tomatoes with green chilies, and cooked pasta, mixing thoroughly to combine.
Reduce heat to low, then mix in the shredded cheese and sour cream until melted and creamy.
Adjust seasoning with salt and pepper, then remove from heat and let sit for a few minutes before serving.
Serve hot, garnished with fresh cilantro if desired.
