The easiest and quickest way to make roasted red pepper pasta sauce is to use jarred red peppers. First, blend the jarred roasted bell peppers in a food processor or a blender with canned tomatoes, almonds, red pepper flakes, olive oil, salt, and garlic. If you use a food processor, your red pepper pasta sauce will be coarser. If you use a high-speed blender, the sauce will turn out smoother. Then cook the sauce on a skillet for 10 minutes before tossing in the pasta.