Cranberry Angel Food Cake Roll

Step 1
Preheat the oven to 300 degrees F (150 degrees C). Lightly coat a 10×15-inch baking pan with nonstick spray. Line the bottom of the pan with waxed paper, then spray the paper.

Step 2
Sift cake flour, 1/2 cup superfine sugar, and salt into a bowl. Sift the mixture two more times.

Step 3
Beat egg whites in a glass, metal, or ceramic bowl until foamy. Gradually add vanilla and cream of tartar, continuing to beat until soft peaks form. Gradually beat in remaining 1/2 cup plus 2 tablespoons superfine sugar. Gradually sift flour mixture over egg white mixture, folding it in until just combined. Spread batter evenly in the prepared pan.

Step 4
Bake in the preheated oven until top of cake is lightly browned and springs back when lightly pressed, about 20 minutes.

Step 5
Remove cake and set on a wire rack. Loosen sides with a spatula, then generously sift confectioners' sugar over top. Cover cake with a clean kitchen towel and invert onto a second wire rack. Remove the pan and peel off the waxed paper. Starting at the short end, roll up the cake and towel together. Place, seam-side down, on a rack and let cool completely, about 1 hour.

Step 6
Simmer cranberries, sugar, and water in a pan over medium-low heat for 5 minutes. Strain well and return to the pan.

Step 7
Whisk in cornstarch; simmer until thick, about 2 minutes. Cover and chill until cake has fully cooled.

Step 8
Very gently unroll the cooled cake. Carefully spread cranberry filling over top, leaving a 1/2 border with no filling. Gently re-roll the cake and place, seam-side down, on a serving platter. Refrigerate for up to 2 hours before serving.