Known for its airy texture, this chiffon cake recipe is made lighter by eight whipped egg whites and flavored with the addition of coffee in the batter. Topped with warmed hazelnut spread and chopped hazelnuts, this lighter-than-air cake makes a great dessert or teatime snack.
In small bowl, combine water and coffee granules; stir to dissolve. Cool slightly.
In large bowl, sift together flour, sugar, baking powder and salt. Add oil, egg yolks, vanilla extract and coffee; whisk until well combined. In large bowl, beat egg whites and cream of tartar with electric mixer to stiff peaks. Fold 1/3 of whipped whites into the batter to lighten. Gently fold in the remaining whites until mixture is combined; do not overmix or batter will deflate. Pour into ungreased pan; tap gently on counter to release air pockets.
Bake 50-60 minutes or until cake springs back when touched. Invert pan immediately onto cooling grid after removing from oven; cool completely (about 2 hours). Run knife around the sides and center of cake to loosen.
In small bowl, heat hazelnut spread in microwave on 50% power for 30 seconds or until warm. Spread over top of cake. Sprinkle with hazelnuts.