Bring a large pot of salted water to a boil. Cook the pasta according to the package instructions. Drain and set aside.

Meanwhile, heat half of the oil in a large pot over medium-high heat. Add the chicken strips and cook for 4-6 minutes, until fully cooked through. Transfer the chicken to a plate and set aside.

Add the remaining oil to the same pot. Add the sliced onion and bell pepper and cook for about 5 minutes, until softened. Stir in the garlic, chili powder, cumin, oregano, and a pinch of salt and pepper. Cook for 1-2 minutes, until fragrant. Stir in the tomato paste and cook for 1 minute more.

Turn off the heat, and return the cooked pasta and chicken to the pot and stir to combine. Then stir in the Greek yogurt and cheese. Once combined, place the pot over low heat and cook just until the cheese is melted and everything is warmed through. If the mixture is too thick, add a small drizzle of water to loosen it.

Season to taste with salt and pepper and serve.