Chocolate Hazelnut Layer Cake

This decadent cake is a dessert-lover's dream، featuring a chocolate batter made with Nutella، buttermilk and hazelnut liqueur، and a smooth frosting of bittersweet chocolate، Nutella and heavy cream.

INGREDIENTS

• 3 c. heavy (whipping) cream
• 2 bar bittersweet chocolate
• 1 c. unsweetened cocoa powder
• c. boiling water
• 1/2 c. Nutella (chocolate hazelnut spread; buy two 13-oz jars)
• 1 c. buttermilk
• 2 tbsp. Frangelico hazelnut liqueur (optional)
• 1 1/2 tsp. vanilla extract
• 1 1/2 c. sugar
• 1 stick butter
• 1 1/2 tsp. baking soda
• 3/4 tsp. baking powder
• 1/2 tsp. salt
• 4 large eggs
• 1 3/4 c. all-purpose flour
• 1 1/2 c. Nutella
• 1 c. hazelnuts
• Garnish: chopped toasted hazelnuts and chocolate curls

DIRECTIONS

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  1. STEP 1Microwave cream in a large bowl on high until steaming. Add chocolate; let stand 5 minutes. Stir until chocolate melts and mixture is smooth. Cover surface directly with plastic wrap; refrigerate until cold، at least 4 hours.
  2. STEP 2Cake: Heat oven to 350°F. You'll need two 9 x 2-in. round cake pans، greased and floured.

1. STEP 3Whisk cocoa powder and water in a medium bowl، then Nutella and buttermilk، Frangelico and vanilla.
2. STEP 4Beat sugar، butter، baking soda، baking powder and salt in a large bowl with mixer on medium-high speed 3 minutes or until pale. Beat in eggs 1 at a time. On low speed beat in flour in 3 additions alternating with cocoa mixture in 2 additions، beating just until blended. Pour into prepared pans.
3. STEP 5Bake 30 to 35 minutes until a pick inserted in centers comes out clean. Cool in pans on rack 10 minutes. Run a knife around edge of each layer; turn out on rack and cool completely.
4. STEP 6Insert several toothpicks halfway up side around both cake layers. Using picks as a guide، cut layers in half with a long serrated knife.
5. STEP 7Filling & frosting: Beat cold chocolate mixture on medium speed until soft peaks form when beaters are lifted. Put Nutella into a bowl; stir in 1 1/2 cups chocolate mixture until smooth. Fold into remaining chocolate mixture until combined. Remove 2 1/2 cups to a bowl; stir in hazelnuts for filling. Reserve remainder for frosting.
6. STEP 8To assemble: Place 1 cake layer on serving plate; spread with 1/3 the filling (1 scant cup). Top with second layer and 1/2 the remaining filling; repeat with third layer and remaining filling. Top with last cake layer. Spread a thin layer of frosting over top and sides; refrigerate 15 minutes to firm. Spread top and sides with remaining frosting. Refrigerate until ready to serve. Garnish just before serving.
7. STEP 9Wrap cooled cake layers and make frosting (through Step 1) up to two days ahead. Cover the frosted cake and refrigerate up to three days.