Preheat oven to 375°F Prepare pasta according to package directions.
While pasta is cooking, heat oil in a medium saucepan over medium heat. Add onion, garlic, and jalapeno and cook until softened, about 3 minutes. Add chili powder and stir for 1 minute. Add tomatoes and liquid, cumin and oregano. Simmer until slightly thickened, about 15 minutes.
When pasta is done, drain well. In bowl, combine pasta, chicken, olives, 3/4 cup cheese and sauce. Spoon into 2-quart baking dish lightly sprayed with cooking spray. Sprinkle remaining cheese on top. Cover loosely with foil and bake until warmed through and cheese is melted, about 15 minutes.