Preheat oven to 375 degrees F. Let pie crust stand according to package directions. Unroll pie crust onto a 12-inch pizza pan. Crimp edges of crust and prick crust evenly with a fork. Bake for 12 to 15 minutes or until lightly browned.
Meanwhile in a large skillet melt butter over medium heat. Add apple slices; cook 5 minutes or until just tender, stirring occasionally. Stir in brown sugar and cinnamon.
In a small bowl stir together 1/2 cup caramel dip, sour cream, and flour. Carefully spread caramel mixture over baked crust. Arrange apple slices over caramel layer. Top with pecans.
Bake about 15 minutes more or until pastry is crisp and golden brown.
In a small bowl, heat 1/4 cup caramel dip in the microwave 30 seconds or just until warm. Spoon caramel over pizza. Cut pizza into wedges and serve warm. If desired, serve with ice cream.