Hazelnut Gâteau Breton

Ingredients

• 1 1/4 cups vanilla sugar
• divided
• 1/2 cup hazelnuts
• lightly toasted
• husked
• 6 large egg yolks (preferably organic)
• 1 cup (2 sticks) salted butter
• melted
• 2 cups unbleached all purpose flour
• 1 large egg yolk beaten with 2 teaspoons water (for glaze)
• Whole strawberries with stems attached or warm strawberry jam

Instructions

1. 1

   Position rack in center of oven and preheat to 325°F.

2. 2

   Butter and flour 9-inch-diameter springform pan.

3. 3

   Combine 2 tablespoons vanilla sugar and hazelnuts in processor; blend until nuts are finely ground but not pasty.

4. 4

   Combine 6 egg yolks and remaining 1 cup plus 2 tablespoons vanilla sugar in large bowl; whisk until well blended and slightly thicker, about 2 minutes (do not use electric mixer).

5. 5

   Whisk in hazelnut mixture.

6. 6

   Gradually whisk in melted butter.

7. 7

   Sift flour over batter; stir just until blended (batter will be thick; do not overmix or cake may be tough).

8. 8

   Transfer batter to prepared pan; smooth top with offset spatula (layer will be thin).

9. 9

   Brush top generously with egg glaze.

10. 10

    Using back of tines of fork, deeply mark crisscross pattern atop cake, marking 3 times across in 1 direction and 3 times in opposite direction.

11. 11

    Bake cake until deep golden on top and tester inserted into center comes out clean, about 1 hour.

12. 12

    Cool in pan on rack 15 minutes, then remove pan sides and cool cake completely.

13. 13

    DO AHEAD Can be made 1 day ahead.

14. 14

    Wrap in foil and store at room temperature.

15. 15

    Cut cake into wedges and serve with whole strawberries or with warm strawberry jam.