Triple Decker Birthday Cake | Williams Sonoma

Ingredients

• 2 3/4 cups (11 oz./345 g) cake flour
• 3 tsp. baking powder
• 1/2 tsp. kosher salt
• 1 cup (8 oz./250 g) unsalted butter, at room temperature
• 1 3/4 cups (14 oz./440 g) granulated sugar
• 4 eggs
• 2 egg yolks
• 2 tsp. vanilla extract
• 1 cup (8 oz./250 g) sour cream
• 2 1/2 cups (10 oz./315 g) confectioners’ sugar, sifted
• 1/2 lb. (250 g) unsweetened chocolate, melted and cooled
• 2/3 cup (6 1/2 oz./200 g) raspberry jam