Coat an 8x4x2-inch or 9x5x3-inch loaf pan with cooking spray or grease bottom and sides lightly with a little cooking oil; set aside. Remove casings from sausage, if present. In a large skillet, cook sausage and the 1/2 cup sweet pepper over medium heat until sausage is brown and pepper is tender, stirring frequently to break up meat. Drain on paper towels; set aside.
For scrapple, in a medium saucepan bring the 2-1/2 cups water to boiling. Meanwhile, in a mixing bowl stir together cornmeal, the 1 cup cold water, and the salt. Slowly add the cornmeal mixture to the boiling water, stirring constantly. Cook and stir until the mixture returns to boiling. Reduce heat to low. Cook, uncovered, for 10 to 15 minutes or until the mixture is very thick, stirring almost constantly with a long-handled wooden spoon. Remove from heat.
Stir in sausage-pepper mixture. Spread the hot mixture evenly into prepared loaf pan. Cool about 30 minutes, then cover and chill at least 4 hours or overnight.
Loosen edges of chilled cornmeal loaf with a metal spatula; turn cornmeal loaf out onto a cutting board. Cut cornmeal loaf crosswise into 1/2-inch-thick slices. Wipe knife clean and moisten with cold water after each cut. (If desired, cut and cook as many slices as you want. Store remainder, wrapped in plastic wrap, in refrigerator up to 3 days.)
Meanwhile for pineapple sauce, coarsely chop enough pineapple to make 2 cups. (Set aside remaining pineapple for another use.) In a medium saucepan combine chopped pineapple and sugar. Bring to boiling; reduce heat and boil gently, uncovered, 15 minutes or until most of the liquid has evaporated and mixture is slightly thickened. Remove from heat. Stir in the 1/4 cup red sweet pepper and the snipped fresh cilantro.
In a large skillet heat cooking oil over medium heat. Cook cornmeal slices 8 to 10 minutes on each side or until brown and crisp. Drain on paper towels. Serve with pineapple sauce. Makes 6 servings.