Preheat oven to 350°F. Line a jelly roll pan with parchment paper.

In a medium bowl, combine together the flour, spices, baking powder, and salt.

Place the egg whites in the bowl of a stand mixer, fitted with a whisk attachment. Whisk until light and foamy. Slowly sprinkle in granulated sugar and continue whisking over medium-high speed until medium peaks form. Transfer to a large bowl and set aside.

Clean your mixer bowl. Add in the yolks, beat over medium-high speed until foamy. Add in molasses and vanilla. Beat until pale, about 3-4 minutes.

Add about a third of the egg whites to the yolk mixture. Combine together using the whisk attachment. Gently fold in the remaining egg whites with a spatula in two separate additions.

Fold in the flour gently in four additions until each time all of the flour has been incorporated. Be careful not to deflate the mixture. Scrape the bottom to check no flour streaks remain.

Pour the batter into the prepared baking sheet. Spread it into an even layer.

Bake for 15-17 minutes until golden.

Meanwhile, prepare a kitchen towel by dusting it with powdered sugar.

Cool for 5 minutes before inverting it onto a kitchen towel dusted with confectioner’s sugar. Peel back the parchment paper, then roll the cake up tightly. Allow to cool completely on a wire rack.

Whip up the heavy cream over high speed for one minute. Add in the powdered sugar and vanilla and continue to whisk on high until the cream is thick.

Once the cake has cooled, gently unroll the cake. Spread the whipped cream on top, leaving a border at the edges.

Roll the cake up, then wrap in plastic and refrigerate for at least 1 hour.

For the white chocolate buttercream, cream butter with cream cheese until fluffy, then add in melted and cooled white chocolate. Add in powdered sugar and vanilla, beating for about 30 seconds.

Spread the white chocolate buttercream over the cake. Using a fork, create a bark-like pattern. Sprinkle with cinnamon sugar.