Preheat broiler.  Cut peppers in half and remove seeds.  Lightly coat the peppers with olive oil, and place cut side down on cookie sheet.  Broil for 10-15 minutes, cool and dice.

     In a saucepan sauté the garlic, onion, and peppers in olive oil for 3-5 minutes.  Mix cornstarch and half & half together well, no lumps.

     Pour the half & half mixture into the onion and peppers in the saucepan.  Use an emersion blender and blend well.  Heat to a boil, stirring until thickens.  Add in the cheese and cook until the cheese has melted.  Stir in butter.  Season with salt and pepper. 

     Serve over ravioli or pasta.