• Preheat oven to 350 F. Grease a 12x18 inch baking pan and line it with parchment paper that extends a little bit up the sides. Grease the parchment as well.
• Sift together flour, 1 cup sugar, baking powder and baking soda in a bowl. Add the salt. In a large bowl, whisk the egg yolks, oil, water and vanilla extract. Add the dry ingredients gradually and stir well. Set this aside.
• In a bowl of a stand mixer (or use a hand-held mixer) beat the egg whites until soft peaks form. Add the sugar gradually as you continue to beat, until the mixture form firm peaks.  Test: If you turn the bowl over, the whipped egg whites should not drip.
• Fold the egg whites into the yolk batter in three additions using a rubber spatula, until the color of the combined mixture is uniform. Pour and scrape the batter into the prepared baking pan. Bake it at 350 F for 12-16 minutes, or until a toothpick inserted at the center of the cake comes out clean.
• Lift the cake by using the parchment paper backing and transfer it onto a wire rack to cool completely.
• Remove the parchment paper backing of the cake: Once the cake is cool, sprinkle powdered sugar all over it. Lay a piece of parchment paper to cover the cake and top that parchment paper with a baking pan of the same size or bigger. Turn everything over, including the wire rack. Remove the wire rack and gently peel off the parchment paper backing. Reposition the parchment paper over the cake and top it with another baking pan. Turn the cake over so that the cake is upright again, resting on an inverted baking pan. You are now ready to fill and roll the cake.
• Pour the dulce de leche over the surface of the cake. Gently spread using an offset spatula so the cake is fully coated with the dulce de leche. Spread the whipped cream all over, but leave about an inch border along the edges to avoid too much cream oozing out upon rolling the cake.
• Roll the cake: Using the parchment paper, lift the short edge of the cake and begin to roll it forward. As you roll forward, move the parchment paper along in the same direction to keep the cake lifted. Continue until you reach the end of the cake. You will be able to wrap the rolled cake with the parchment paper. Pat and shape the cake to reinforce its shape. 
• Transfer the cake onto serving plate ate gently unwrap it. Trim the edges to make it neat, if you prefer. Refrigerate the cake for at least 2 hours. After chilling, spoon the excess dulce de leche drippings over the cake., and drizzle more dulce de leche if you desire. Serve.

Make the Whipped Cream

• In a bowl of a stand mixer, pour the cream. Beat on high speed until thick and fluffy.