For the Buckwheat Crepes: Combine eggs, sugar, flours, and melted butter and blend in blender. Add in cognac. Spray the bottom of a nonstick pan and lightly heat. Using about one 1/4 oz of mix ladle in center of pan and move pan around so it evenly coats the bottom of the pan in a thin layer. Flip and set aside stacking with wax paper or parchment. In a separate pan, heat until hot and add seasoned foie gras. When melting, add Tuscan cabbage and fresh nutmeg. Finish with Brunoise vegetables, season with salt and pepper to taste and fill up crepes with the vegetable mixture.
For The Mulberry Jus: Make a gastrique by cooking down in a saucepot the sugar, red wine vinegar and mulberries. When reduced to a syrup, add in the glace and strain through a chinois. Arrange on plates with greens. Sprinkle chopped hazelnuts over the salad and drizzle hazelnut oil. Serve with grissini if available.