Preheat oven to 350°F. Bring prunes and water to a boil in a small saucepan; reduce heat and simmer for 10 minutes, stirring frequently, until mixture is very thick and liquid has been absorbed; let cool. Spray a 9 inch springform pan liberally with nonstick cooking spray then coat with 2 Tbsp sugar, shaking out excess. Beat together remaining sugar, buttery spread, milk, extract, egg whites and prunes in a medium bowl for 3 minutes on high speed with an electric mixer. Beat in dry ingredients on low speed, then beat for a few minutes on high to make a light batter. Spread in prepared pan and bake for 40 to 45 minutes or until a toothpick inserted in the center comes out clean. To serve, drizzle serving plates with a little melted jam, add slice of cake and drizzle with chocolate.