Prepping:

1.  Preheat oven to 375°F.
2.  Grease 2 Jelly roll pans.  Place parchment inside each pan and also grease parchment paper.
3.  Squeeze lemon sections to yield ⅓ cup of lemon juice, using a lemon squeezer.
4.  In a bowl, add the dry ingredients – flour, baking powder and salt.

Making the Cake Batter:

1.  With a hand mixer, beat the egg yolks at low speed until a pale-yellow creamy texture is formed.
2.  Beat the egg whites at medium speed until a foamy texture is formed.
3.  Gradually add ½ cup of sugar in small amounts at medium speed.  Continue this process until all the sugar has been added to the egg whites.
4.  After adding all the sugar, increase the speed to medium high until stiff peaks are formed.
5.  Add small amounts of the beaten egg yolks around the inside edge of bowl.  Insert rubber spatula to the bottom of bowl and gently fold over to the top center.  Continue this process until beaten egg yolks are fully incorporated.
6.  Using a strainer, sift the flour mixture on top of egg mixture and gently fold.
7.  Pour vanilla extract around the inside edges of mixing bowl and then gently fold into cake batter.

Spreading and Baking the Cake Batter:

1.  Place one half of cake batter on top of each greased pan.  Spread evenly on top and to all the corners with an icing spreader.
2.  Bake both pans at 375°F for 15 minutes or until golden brown on top.
3.   Remove baked sponge cakes from oven and slightly cool.

Preparing the Guava Filling:

1. In a food processor, add the chunks of guava paste and ⅓ cup lemon juice.
2. Mix the ingredients at medium speed until a smooth consistency is formed.

Rolling and Spreading Guava Filling:

1.  Run a knife around the inside edge of each pan.
2.  Place damp towels on countertop and dust with powdered sugar.
3.  Invert each pan onto damp towels and then carefully peel parchment paper and discard.
4.  Roll each sponge cake with damp towel, starting with the short end.  Completely cool at room temperature.
5.  Unroll each sponge cake once completely cooled.  Place several spoonsful of guava filling on top and then spread with an icing spreader.
6.  Leave approximately ¼-inch border along the sides of sponge cake.
7.  Reroll each sponge cake without the damp towels.
8.  Wrap each one with plastic wrap and refrigerate seam-side down to chill for at least 1 hour.
9.  Unwrap each sponge cake and then dust with powdered sugar.  Trim off both ends before serving.