Preheat your oven to 350°F (175°C) and line a 10x15 jelly roll pan with parchment paper.

In a bowl, whip egg whites until they reach stiff peaks, about 3-5 minutes.

Combine all-purpose flour, baking powder, salt, ground ginger, nutmeg, and cinnamon in a separate bowl.

Mix egg yolks, brown sugar, granulated sugar, and vanilla extract in a stand mixer on low speed for 2-3 minutes. Add yogurt and molasses, mix until smooth.

Fold in dry ingredients gently to the wet mixture.

Incorporate whipped egg whites carefully into the batter.

Pour and spread the batter evenly in the prepared jelly roll pan.

Bake in the oven for about 10 minutes until edges are lightly browned.

Cool the cake, then roll it in a powdered sugar-dusted towel.

Prepare filling by whipping mascarpone cheese with vanilla and powdered sugar until smooth.

Unroll cake, spread filling, and re-roll tightly.

Prepare meringue frosting by heating egg whites and sugar in a double boiler, then whip to stiff peaks.

Frost the cake with meringue and create texture to mimic a log.

Decorate with cranberries and rosemary.