Preheat oven to 350℉. Grease a 15 x 10-inch sheet pan (jelly roll pan), and line with parchment paper.
In a medium bowl whisk to combine flour, cocoa powder, baking powder, and salt. In a large bowl vigorously whisk together eggs, sugar, and Stevia In The Raw®, until mixture is thickened and light yellow. Whisk in butter and vanilla. Fold in dry ingredients just until combined.
Scrape batter into prepared pan and spread evenly. Bake until cake is set, 10-13 minutes. Do not overbake or the cake will dry out.
Run a thin knife along the pan edge to release cake from pan. Place a piece of parchment paper on a countertop and invert cake onto parchment. While cake is still hot, roll up cake tightly in parchment, starting at a short end. Let cake cool completely rolled up.
In a large bowl or the bowl of a stand mixer fitted with the whisk beat cream, crème fraîche or mascarpone, Stevia In The Raw®, and peppermint extract on medium until stiff.
Unroll cake and spread evenly with peppermint cream, leaving a ¾” border all around. Re-roll cake tightly but not so tightly that filling oozes out. Wrap in plastic wrap and refrigerate at least 1 hour before serving.
Right before serving, dust cake with cocoa powder and sprinkle with peppermint candies.