Heat oil in large skillet over medium-high heat. Add red pepper, green pepper, onion and salt; cover and cook over low heat until very tender, about 8 minutes. Remove from heat and cool slightly.
Heat oven to 350°F. Grease 9 x 5 x 3-inch loaf pan.
Combine bread and milk in large bowl; let stand 5 minutes to soften. Add beef, crumbs, ketchup, egg, hot-pepper sauce and sweet red pepper mixture; toss gently to mix. Spoon and pat into prepared loaf pan.
Bake in 350°F oven for 1 hour. Let stand for 15 minutes before serving. Top each serving with dollop of Sweet Pepper Sauce and serve with Spicy Mashed Potatoes.
Heat oil in large skillet over medium-high heat. Add red pepper, green pepper, onion, water and salt; cook, stirring occasionally, over medium heat until very tender, about 8 minutes. Stir in vinegar, brown sugar and mustard seeds; cook over medium-high heat until most of liquid has evaporated and sauce is thickened, about 8 minutes.