Prepare sponge cake according to manufacturer's instructions. Line half sheet trays with parchment paper and deposit 1 lb. prepared cake batter in each. Spread evenly with an offset metal spatula. Bake at 350°F until cake is golden brown and springs back lightly when touched. While cake is still warm, invert it onto a freshly cleaned side towel and peel off parchment paper. Roll the cake up, using the towel in between. Let cake cool completely. After cake is cool, gently unroll and using a #6 white scoop, place 2 scoops of filling on prepared cake. Spread to edges and roll back up. Dust with powdered sugar.
Rolling the cake on a towel rather than parchment paper allows the cake to breath as it cools, allowing greater flexibility when filling and rolling back up.
Jelly Roll, Sponge, Dulce de Leche, Caramel, Pineapple, Guava, Powdered Sugar, Donut Sugar