Mix base cake and butter; press firmly onto bottom of full hotel pan. Sprinkle with coconut and OREO Pieces.
Pour sweetened condensed milk evenly over ingredients in pan.
Bake in 350°F-conventional oven for 20 to 25 minutes or until lightly browned. Cool completely.
Spread with preserves; sprinkle with pecans. Drizzle with white chocolate. Cool completely. Cut into 48 bars.
For each serving: Cut 1 bar diagonally in half. Arrange on side of dessert plate; place 3 scoops of ice cream on other side of plate. Drizzle with 1 Tbsp. chocolate topping.