How to Make It
Prepare Cake Layers: Preheat oven to 350°. Beat first 2 ingredients at medium speed with an electric mixer until light and fluffy. Add eggs, 1 at a time, beating just until blended after each addition.
Stir together flour and next 2 ingredients. Stir together buttermilk and baking soda in a 2-cup glass measuring cup. Add flour mixture to butter mixture alternately with buttermilk mixture, beginning and ending with flour mixture. Beat at low speed just until blended after each addition.
Stir jam until smooth. Add jam and vanilla to butter mixture, and beat at low speed just until blended. Stir in toasted pecans and grated apple. Spoon batter into 4 greased (with shortening) and floured 9-inch round shiny cake pans (about 2 1/2 cups batter in each pan).
Bake at 350° for 20 to 22 minutes or until a wooden pick inserted in center comes out clean. Cool in pans 10 minutes; remove from pans to wire racks, and cool completely (about 30 minutes).
Prepare Frosting: Beat cream cheese and 1/4 cup softened butter at medium speed with an electric mixer until creamy. Add dulce de leche, 1 can at a time, beating until blended after each addition. Gradually add 2 Tbsp. whipping cream, 1 Tbsp. at a time, and beat at medium speed. Add up to 2 Tbsp. additional cream, 1 Tbsp. at a time, and beat until frosting is desired spreading consistency. Spread frosting between each layer and on top and sides of cake.
We tested with Nestlé La Lechera Dulce de Leche.