Preheat oven to 400°F. Coat a 9-inch baking pan with cooking spray. Place bananas in pan.
In a small bowl, combine pineapple, 1 tablespoon of Splenda and cinnamon; pour over bananas. Cover pan with foil and bake for 30 minutes. (Note: The canned pineapple is already sweet so omit the Splenda if you prefer.)
Meanwhile, in another small bowl, combine ricotta, remaining tablespoon of Splenda and vanilla; set aside.
Place one baked banana in each of four individual serving bowls and top each with about 2 tablespoons of pineapple sauce and 1/4 cup of ricotta mixture. Top each with 1/4 cup of raspberries. Serve immediately. Yields 1 banana split per serving.