Line a 9x5x3-inch loaf pan with plastic wrap, allowing plastic wrap to hang over edges of pan; set aside. In a large saucepan bring the water and salt to boiling. Slowly stir in oats. Return to boiling; reduce heat to medium-low. Cover and simmer for 30 minutes or until creamy, stirring occasionally.
Meanwhile, in a large skillet cook the sausage, sweet pepper, and onion until sausage is no longer pink. Drain off fat. Pat sausage mixture dry with paper towels. Stir cooked sausage mixture into oat mixture. Cool 30 minutes. Spoon mixture into prepared loaf pan. Cover and refrigerate overnight.
Preheat oven to 450 degree F. Line a baking sheet with foil; generously coat with cooking spray and set aside. Remove sausage-oat mixture from pan by lifting up on plastic wrap; invert onto a cutting board and remove plastic wrap. Cut loaf crosswise into eight 1-inch-thick slices. Brush both sides of slices with some of the oil. Place slices on prepared baking sheet. Bake for 30 minutes or until lightly browned and heated through, turning slices halfway through baking time. Makes 8 servings.