Eighteen-Layer Brazilian Guava Cake Roll (Bolo de Rolo)

Directions

1. Measure ingredients for the batter and set aside.
2. Prepare the filling. Add guava paste, water, and port, if using, to a non-stick medium pan and bring to a boil over medium-high heat, stirring well until guava paste is fully melted and mixture is homogeneous and smooth. Strain through fine mesh sieve if chunky. Remove from heat, let cool, and divide into 9 portions. Set aside.
3. Next, prepare the batter: In the bowl of a mixer fitted with the paddle attachment, beat butter at medium speed for about 2 minutes. At a slow speed, gradually add the sugar, then beat for 3 to 5 minutes, or until mixture is homogeneous and creamy. Add the yolks one by one, beating at low speed after each addition until just incorporated.
4. At low speed, gradually add flour until you have a homogenous batter. You may have to scrape down the batter from the sides of the bowl a few times.
5. With a spatula, gently fold in the egg whites (do not beat). Preheat the oven to 350° F.
6. Grease and flour 9 (10- by 15-inch) jelly roll pans and pour about 1 cup of batter into each. (If you are short on baking sheets, you can wash and dry the baking sheet, repeating the process of unmolding and rolling as described below as each layer of cake bakes.)
7. Use an offset icing spatula to spread the batter into a very thin and uniform layer covering the bottom of each sheet pan. Bake the first layer of cake for 3 1/2 to 4 minutes; do not let the cake brown.
8. Remove from the oven and place baking sheet on a counter lined with a kitchen linen or towel. Since this cake is thin and delicate, here is a great technique to release it from the pan without breaking the layer: Gently run a butter knife around the edges to loosen the cake from pan, making it easier to unmold. Next, sprinkle the top of cake with 2 tablespoons of sugar and spread a kitchen towel on top. Then place an empty and larger baking sheet pan on top of this, right side up, to sandwich the cake and towel between the two pans. Finally, flip the whole assemblage over in order to release the cake from the pan in which it was baked. Remove what is now the top baking sheet pan, and then gently slide the bottom pan from beneath the cake and towel. Working quickly, spread melted guava paste mixture on top of the cake and then roll: Starting from one end, pull up the two adjacent corners along the short length of the towel to initiate rolling of the edge of the cake. Continue supporting/pushing the rolling edge of the cake with the towel beneath as needed until the cake layer is completely rolled. The cake rolls more easily while still warm. Reserve rolled cake layer covered with towel.
9. Each rolled cake is then rolled into the next subsequent sheet of cake that has been spread with the guava paste. If any breaks appear in cake, press break with fingers to seal while it is still warm, and sprinkle more sugar on top. Slice the 2 edges of the cake to remove rough, imperfect ends. Serve cake roll sliced into thin slices by itself, with a slice of Edam cheese, or slightly warm with a scoop of vanilla or coconut ice cream.
10. NOTES: 1) For easier handling, you can make 3 smaller cake rolls using the same recipe: To do this, make three rolls with three layers each. 2) Guava paste is available in the Latin aisle of many different supermarket chains such as Walmart, as well as in virtually any Latin market. Alternatively, the guava paste filling can be substituted by thin layers of Nutella or dulce de leche/caramel spread.
11. STORAGE: You can store in the refrigerator for about 1 week, or at room temperature, covered in parchment paper or plastic wrap, for up to 3 days. Cake can be frozen for up to 1 month.