– 1 (22 ounce) can lemon pie filling – 1 lemon cake mix (I used Betty Crocker Delights Super Moist Lemon Cake mix) – 1 (8 ounce) package cream cheese, room temperature – ¼ cup granulated sugar – 3/4 cup unsalted butter, thinly sliced (1 1/2 sticks) – whipped cream (optional)