Foolproof Jelly Roll Cake

1. Adjust oven rack to lower-middle position and heat oven to 350 degrees. Grease 18 by 13-inch rimmed baking sheet, line with parchment paper, grease parchment, then flour sheet. Grease second large sheet of parchment and set aside. Whisk flour, baking powder, and salt together in medium bowl; set aside.
2. Using stand mixer fitted with whisk, whip eggs on medium-high speed and gradually add granulated sugar and then vanilla, about 1 minute. Continue to whip mixture until very thick and voluminous, 4 to 8 minutes. Sift flour mixture over egg mixture and fold in with rubber spatula until just incorporated.
3. Scrape batter into prepared baking sheet and spread out to even layer. Bake cake until it feels firm and springs back when touched, 12 to 17 minutes, rotating baking sheet halfway through baking. Lay clean kitchen towel on work surface.
4. Immediately run knife around edge of cake, then flip hot cake out onto towel. Peel off and discard parchment baked on bottom of cake. Starting from 1 short end of cake, roll cake and towel snugly into log and let cool, seam side down, for 15 minutes.
5. Gently unroll cake. Spread jam over cake, leaving 1⁄2-inch border at edges. Reroll cake gently but snugly around jam, leaving towel behind as you roll. Trim ends of cake, transfer cake to serving platter, and let cake cool completely, about 30 minutes. Dust with confectioners’ sugar before serving.

Any flavor of seedless jam will work here; for an added treat, sprinkle 2 cups fresh blueberries, raspberries, blackberries, or sliced strawberries over the jam before rolling up the cake.

ASSEMBLING A JELLY ROLL CAKE
1. Starting from short side, roll cake—towel and all—into jelly roll shape. Cool for 10 minutes.
2. Unroll cooled cake. Using offset spatula, spread jam over surface of cake, leaving 1⁄2-inch border around edges. Sprinkle half of raspberries over cake, if using.
3. Reroll cake gently but snugly around filling, carefully peeling off towel as you roll. Dust top of cake with confectioners’ sugar.
4. Trim thin slices from both ends and then cut cake into individual slices, using electric or serrated knife. Garnish with raspberries, if using.