If not using jarred roasted peppers, first roast them and let them cool. To roast: lightly coat in olive oil, place in a preheated oven at 450*F for 20 minutes, then flip them and roast another 20. Remove from the oven, let them cool, and peel off the skin and remove the seeds.
Add all other ingredients to a food processor and blend until smooth.
Serve immediately or store in the refrigerator up to 5 days, or freeze up to two months.
Notes
These ingredients are widely variable in amounts depending on your taste. If you want more of a roasted pepper taste and less basil, go with that. If you like really garlicky, add another clove or two. I personally don't care for black pepper, so I omit it. You can't really go wrong with this recipe so don't be nervous.... just have fun with it!