Heat olive oil in a small sauce pot. Add garlic and sauté for one minute (do not brown). Add bell peppers and sauté until al dente. Add olives and capers and stir. Add red wine and bring to a boil.
Add remaining ingredients except basil. Bring to a boil, reduce to low heat and simmer for approximately 30 minutes. Add basil to sauce and stir well. Remove Siena sauce from heat. Serve over your favorite pasta. Garnish with chopped basil, if desired.