Heat oven to 350 degrees. Spray 9x9 square pan with nonstick cooking spray.
Place pineapple in a food processor and pulse a few times to chop coarsely, I used slices and placed them in the bottom of the pan whole. Do not puree, the fruit should be thick with some visible fibers. Reserve 1/4 cup of the pineapple juice. Pour the rest of the pineapple into the baking pan in an even layer. Sprinkle with Splenda Brown sugar blend. In a medium size bowl combine flour, Splenda sweetener, add margarine, egg substitute, skim milk, vanilla and reserved pineapple and mix on low speed until combined. Pour into pan. Bake for 40 minutes or until firm in the middle when touched.