There are quite a few recipes that call for only egg yolks. Try making a custard, creme brulee, pudding, ice cream, lemon curd, tiramisu, and more. For something savory, pasta carbonara is a simple, delicious entree.
3 egg yolks - Classic Tiramisu 4 egg yolks - White Chocolate Creme Brulee 5 egg yolks - Caramel Swirl Ice Cream 6 egg yolks - Chocolate Pots de Creme 7 egg yolks - Classic Creme Brulee