A flavorful, simple sauce that is great for weeknights. Pair with Italia Tocai or Pinot Grigio.
In a small skillet cook the garlic, the onion, the red pepper flakes, the thyme, and salt and pepper to taste in the oil over moderately low heat, stirring, until the onion is softened, add the bell peppers and the broth, and simmer the mixture, covered, for 10 minutes, or until the peppers are very soft. In a blender purée the mixture until it is smooth, return it to the skillet, and swirl in the butter. Stir in the basil, the lemon juice, and salt and pepper to taste and keep the sauce warm.
In a kettle of boiling salted water cook the fettuccine for about 5 minutes, drain it well, and transfer it to a serving bowl. Add the sauce, toss the pasta well, and serve it with the Parmesan.