Classic Yellow Layer Cake with Fudge Filling
Yield: 1 8 inch layer cake.
 
Ingredients
For the Cake:
  • 3½ cups sifted cake flour
  • 1 tablespoon baking powder
  • 1 teaspoon salt
  • 1 cup (2 sticks) butter, softened
  • 2 cups granulated sugar
  • 4 eggs, room temperature
  • 2 teaspoons vanilla extract
  • 1 cup milk
Fudge Filling:
  • 1⅔ cups milk, divided
  • 4 egg yolks
  • 3 tablespoons cornstarch
  • ½ cup granulated sugar
  • Pinch of salt
  • 4 tablespoons butter, cut into tablespoons
  • 4 ounces semi-sweet chocolate, finely chopped
  • 1 teaspoon vanilla extract
Buttercream:
  • 3 sticks butter, softened
  • 11/2 teaspoons vanilla extract
  • 6 cups sifted confectioners' sugar
  • 3 tablespoons milk or water
Instructions
For the Cake:
  1. Preheat oven to 350° F. Grease/flour 2 8-inch cake pans.
  2. In large bowl, stir together flour, baking powder and salt. Set aside.
  3. In another large bowl, beat butter and sugar with electric mixer until light and fluffy. Add eggs and vanilla; mix well.
  4. Add flour mixture alternately with milk, beating well after each addition. Continue beating 1 minute. Pour into prepared pans.
  5. Bake 35-40 minutes or until toothpick inserted in center comes out clean. Cool on a wire rack for 15 mins and then remove the cake from pan and cool completely.
For the Filling:
  1. In a large bowl, whisk ⅔ cup milk, egg yolks and cornstarch until smooth. In large saucepan, stir together remaining milk, sugar and salt until well combined. Cook over medium heat until steaming, but do not boil.
  2. While whisking, slowly stream about half of hot milk into egg yolk mixture to warm. Transfer back into saucepan. Continue cooking, stirring constantly, until mixture thickens and boils.
  3. Remove from heat and stir in butter, chocolate and vanilla extract. Cover top directly with plastic wrap and chill in refrigerator until completely cool.
For the Frosting:
  1. In large bowl, beat butter with electric mixer until light and fluffy. Beat in vanilla.
  2. Gradually add sugar, one cup at a time, beating well on medium speed. Scrape sides and bottom of bowl often. When all sugar has been mixed in, icing will appear dry.
  3. Gradually add milk; beat at medium speed until light and fluffy.
  4. Keep bowl covered with a damp cloth until ready to use.
To assemble:
  1. Use a serrated knife to torte the cake, slicing each layer horizontally making 4 even layers.
  2. Pipe some buttercream around the edge of the first layer and then spread with fudge filling. Add another layer of cake and repeat, lining the layer with frosting and then filling with the fudge.
  3. Leave the last layer on top, with the flattest side down. Spread frosting around the top and sides of the cake. Pipe stars around the edge if desired and top with sprinkles.
Notes
Recipe from Craftsy.
Recipe by The Baker Chick at https://www.thebakerchick.com/classic-yellow-layer-cake-with-fudge-filling/