For a change, I love to cook this pasta cooked in spicy tomato sauce. Pasta w/Spicy Tomato Sauce has slightly tangy and sweet flavor. Besides prawn, that I'd added you can opt for chicken pieces. Throw in some vegetables of your choice, this has became a complete meal by itself..
For chili paste, you can buy a tub from supermarket or make your own using 10-15 dried chili, soak in hot water for a few minutes then drain and blend. If you love spicy food, it is economical to grind a lot more for future use.
In case you are vegetarian, do omit the prawn/ chicken, replace them with tofu.