Roast the peppers. This can be done under the broiler, open flame or a hot cast iron plate/ skillet. Using the preferred method above roast the peppers for a few minutes on each side until charred and the skins are black. The more smoke you create the better the flavor will be.
4 red bell peppers
Once your peppers have been charred on all sides carefully transfer them to a bowl and cover tightly with plastic wrap or aluminum foil until cool enough to handle.
Once cool enough to handle peel the peppers and discard the peels and core with the seeds. Transfer cleaned peppers to a powerful blender or food processor.
Meanwhile preheat a small skillet over medium heat and sauté the onion or shallots in a light drizzle of olive oil until softened. Add in the garlic and chili flakes and sauté until you can smell the garlic taking care not to burn it. Remove from heat and transfer to the blender with the peppers.
1/4 red onion, 2 garlic cloves, 1 pinch red pepper flakes
Add the olive oil, vinegar and salt and process until silky smooth. Taste and adjust seasonings with more salt, vinegar and chili flakes to taste.
1/4 cup extra virgin olive oil, 1.5 Tbsp red wine vinegar, 1/2 tsp sea salt
Meanwhile cook the pasta according to package directions until al dente. Toss with the pepper sauce until coated well and serve garnished with fresh basil, chopped onion chives and red chili flakes.
3/4 lb pasta, basil