Cook the pasta: Bring a large pot of salted water to a boil.
Cook the pasta according to package directions until al dente. Reserve 1/2 cup pasta water, drain, and set aside.
Season the chicken: In a bowl, toss the chicken with 1/2 teaspoon salt, 1/4 teaspoon black pepper, chili powder, cumin, smoked paprika, oregano, and cayenne if using. Coat well.
Sear the chicken: Heat a large skillet over medium-high and add the olive oil.
Add the chicken in a single layer and cook 4–6 minutes, stirring once or twice, until browned and cooked through. Transfer to a plate.
Cook the vegetables: In the same skillet, add onion and bell pepper. If the pan looks dry, add a splash more oil.
Cook 3–4 minutes until softened. Stir in garlic and cook 30 seconds until fragrant.
Build the sauce: Add corn, black beans, and the drained fire-roasted tomatoes. Stir in the chicken broth and bring to a gentle simmer for 2–3 minutes to marry the flavors.
Make it creamy: Reduce heat to low.
In a small bowl, whisk Greek yogurt with lime juice and a spoonful of warm sauce from the skillet to temper it. Stir the yogurt mixture into the skillet until smooth. Do not boil after adding yogurt.
Combine with pasta: Return the cooked chicken to the skillet along with the pasta.
Toss gently until everything is evenly coated. If the sauce seems thick, add a splash of reserved pasta water to loosen.
Finish and taste: Stir in cilantro. Taste and adjust salt, pepper, and lime.
For extra richness, add a light sprinkle of cheese if you like.
Serve: Top with avocado, green onions, or cotija. Serve warm and enjoy.