- 1 cup unsalted butter (250 ml, softened)
- 1 cup sugar (divided)
- 3,072 grams eggs (separated)
- 3/4 cup hazelnuts (roughly chopped)
- 1 cup all-purpose flour
- 1/4 teaspoon kosher salt
- 1 cup chocolate-hazelnut spread
- Preheat oven to 350°F. Coat 12 miniature loaf pans with nonstick pan spray.
- Add butter and ½ cup sugar to bowl of KitchenAid® Artisan Mini Stand Mixer. Attach bowl and Flat Beater to mixer. Turn to Speed 4 and beat 5 minutes or until light and fluffy. Continuing on Speed 4, add egg yolks, one at a time, beating well after each addition. Stop and scrape bowl. Add hazelnuts and flour. Turn to Speed 2 and mix until well blended. Transfer mixture to large bowl. Clean and dry mixer bowl.
- Add egg whites to mixer bowl. Attach bowl and Wire Whip to mixer. Gradually turn to Speed 10 and whip until egg whites are opaque and beginning to hold their shape. Gradually add remaining ½ cup sugar and whip until whites hold soft (but not stiff), slightly glossy peaks.
- Stir one fourth of egg white mixture into hazelnut mixture to lighten the batter. Add remaining egg white mixture and fold in gently with spatula just until blended. Remove one fourth of batter to separate bowl; add chocolate hazelnut spread. Fold in gently with spatula.
- Fill each loaf pan one fourth full with yellow batter. Top each with a thin layer of the chocolate batter, followed by another layer of yellow batter. Fill each pan no more than three fourths full.For a marbled effect, use a toothpick to swirl batter in circles.
- Bake 35 to 45 minutes or until toothpick inserted in centers comes out clean.