For Nut Roll:- use first 4 ingredients on the list.
Preheat oven to 350°F
Grease a jelly roll pan, line with paper, and grease. Beat yolks with sugar until thick. Mix baking powder with nuts and fold into yolks. Whip egg whites until stiff and fold into batter. Spread in prepared pan and bake about 20 minutes. Cover cake with a damp towel, and chill in refrigerator. Turn cake out on the towel, and remove paper. Spread the filling and roll (like a jelly roll). Dust with powdered sugar and chill.
This freezes well or can be kept up to three or four days in the refrigerator. Just be sure that it does not sit at room temperature except briefly when slicing and serving.
For Lemon Curd Filling:- use last 6 ingredients.
Combine lemon juice and starch in heavy saucepan. Stir until dissolved (bring to a boil to thicken and remove floury taste). Carefully whisk in remaining ingredients. Cook over medium heat until thick and smooth and just beginning to boil. Stir constantly about 7 minutes and transfer to a bowl. Cover the surface with plastic wrap. Chill.