Cook the elbow macaroni according to package instructions until al dente. Drain and set aside.
In a small bowl, mix chili powder, ground cumin, smoked paprika, garlic powder, salt, and black pepper.
Heat olive oil in a large skillet over medium-high heat. Add the chicken strips and sprinkle the spice mixture over them. Cook for 5-7 minutes, stirring occasionally, until the chicken is cooked through and lightly browned. Remove chicken from skillet and set aside.
In the same skillet, add the sliced red, green, and yellow bell peppers, onion, and minced garlic. Sauté for 5-6 minutes until the vegetables are tender-crisp. Remove from heat.
In a medium saucepan, melt the butter over medium heat. Whisk in the flour and cook for 1-2 minutes until lightly golden, stirring constantly.
Gradually whisk in the milk, continuing to whisk until the mixture thickens and comes to a simmer, about 4-5 minutes.
Remove the saucepan from heat and stir in the shredded cheddar and Monterey Jack cheeses until melted and smooth.
Stir in the Greek yogurt and fresh lime juice until well combined. Season the cheese sauce with salt and black pepper to taste.
Add the cooked macaroni, sautéed vegetables, and cooked chicken to the cheese sauce. Stir gently to combine everything evenly.
Sprinkle chopped fresh cilantro over the top and serve immediately.