Heat oven to 350ºF. In 1 quart saucepan, melt butter and cream over low heat, stirring occasionally, and set aside. In large mixing bowl, combine sugar and eggs. beat with electric mixer on medium speed, scraping bowl often until well mixed. Add butter mixture, flour, baking powder and salt. Continue beating, scraping bowl often until smooth. By hand, stir in apples and blueberries. Spread into greased and floured 13x9" baking pan. Bake 45-55 minutes or until wooden pick inserted in center comes out clean. Serve warm with sweetened whipping cream. Yield:15 servings.