Preheat your oven to 350°F (175°C) and prepare a 10×15 jelly roll pan lined with parchment paper.

In a stand mixer, whip the egg whites on high speed until stiff peaks form (2-3 minutes).

Whisk egg yolks, brown sugar, granulated sugar, and vanilla extract together until smooth and creamy.

In another bowl, sift all-purpose flour, baking powder, ground ginger, cinnamon, and nutmeg together.

Gradually add the dry mixture to the egg yolk mixture, followed by plain yogurt and molasses.

Gently fold the whipped egg whites into the batter in three additions until no white streaks remain.

Spread the batter in the prepared jelly roll pan and bake for 10 minutes or until lightly browned.

Dust a clean kitchen towel with powdered sugar and invert the baked cake onto it. Roll the cake tightly with the towel and cool for 1-2 hours.

Prepare sugared cranberries by dunking fresh cranberries in simple syrup and rolling them in granulated sugar.

Unroll the cooled cake and spread a layer of mascarpone cheese over it.

Roll the cake back up without the towel and wrap it in plastic wrap. Refrigerate for 30 minutes to 1 hour.

Prepare meringue frosting by whisking egg whites and powdered sugar over simmering water until sugar dissolves. Whip until stiff peaks form.

Frost the rolled cake with meringue using a spatula and optionally toast the edges with a culinary torch.

Garnish with sugared cranberries and fresh rosemary before serving.