Preheat Oven To 300 Degrees F (150 Degrees C). Bring A Large Pot Of Lightly Salted Water To A Boil. Add Pasta And Cook For 8 To 10 Minutes Or Until Al Dente; Drain. Meanwhile, In Large Skillet, Saute Chile Pepper, Bell Pepper And Onion Until Soft. Add Tomatoes, Puree And Chili Powder And Cook 2 Minutes More. For A Smooth Sauce, Puree With A Hand Blender, Or Puree In Batches In Food Processor. Combine Pasta And Sauce In 9 X 13 Baking Dish And Bake For 15 Minutes. Serve Hot.