Lemon Blueberry Jelly Roll

This is a not-too-sweet, not-too-difficult summer fresh cake to make. Cut the jelly roll in half width-wise immediately after baking to make two smaller jelly rolls.

Lemon Jelly Roll
4 large eggs, separated, at room temperature
1/2 cup granulated (white) sugar
1 cup all-purpose (plain) flour
2 teaspoons baking powder
zest of one large lemon
1/4 cup lemon juice

Preheat oven to 375◦F. Line a 10x15 inch jelly roll with parchment paper.
Beat the egg whites to soft peaks. Gradually beat in the sugar until mixture is glossy and holds stiff peaks. Beat in the egg yolks, one at a time. Fold in remaining ingredients.
Spread batter evenly in prepared pan. Bake ten minutes. Cook five minutes.

Flip cake onto a clean tea towel lined with parchment paper that is sprinkled with sifted icing sugar. Sift more icing sugar on top. Tightly roll the cake with the paper and tea towel. Allow to cool completely. Gently unroll cake, spread with blueberry jam, and reroll cake. Chill until firm, then slice with a serrated knife.