Step 1

Preheat oven to 350°F. Melt 2 Tbsp. butter in a large skillet over medium-high heat; add apples; sauté 5 minutes or until softened. Remove from heat; cool completely (about 30 minutes).

Step 2

Meanwhile, prepare Streusel Topping and Caramel Sauce.

Step 3

Beat remaining ½ cup butter at medium speed with an electric mixer until creamy; gradually add sugar, beating well. Add eggs, 1 at a time, beating until blended after each addition.

Step 4

Whisk together flour, baking powder, and salt; add flour mixture alternately to butter mixture with milk, beginning and ending with flour mixture. Beat at low speed until blended after each addition. Stir in vanilla.

Step 5

Pour batter into a greased and floured 9-inch springform pan; cover top of batter with apples. Drizzle with ½ cup Caramel Sauce (reserve the rest); sprinkle with Streusel Topping.

Step 6

Bake at 350°F for 45 minutes. Cover loosely with aluminum foil to prevent excessive browning; bake 25 to 30 more minutes, or until center is set. (A wooden pick will not come out clean.) Cool in pan on a wire rack 30 minutes; remove sides of pan. Cool completely on wire rack (about 1 ½ hours). Drizzle top of cake with remaining ½ cup Caramel Sauce before serving.