Preheat your oven to 325°F (163°C). Line the bottom of a 9-inch springform pan with parchment paper and grease the sides. Mix the shortbread crumbs, sugar, cinnamon, and melted butter until it looks like damp sand, then press it firmly into the bottom and slightly up the sides of the pan. Bake for 10 minutes, then set it aside to cool. Once cooled, wrap the outside of the pan tightly in two layers of heavy-duty foil (or use a silicone/oven bag) so water from the bath can't seep in.

Lower the oven to 300°F (148°C). Beat the cream cheese, brown sugar, and flour on low speed until smooth, scraping the bowl as you go. Keep the mixer on low the whole time — higher speed whips in air that causes cracking as the cheesecake bakes and cools.

Mix in the sour cream, molasses, vanilla, ginger, cinnamon, nutmeg, and cloves on low speed until just combined, scraping the bowl well.

Add the eggs one at a time on low speed, scraping the bowl after each addition, to avoid overworking the batter.

Pour the filling over the crust and smooth the top. Set the wrapped pan in a larger pan with warm water halfway up the sides, below the foil line. Bake 1 hour 20 minutes. The center should still look slightly jiggly — it firms up as it cools.

Turn off the oven and leave the cheesecake inside with the door closed for 30 minutes, then crack the door and leave it another 30 minutes before removing. This gradual cooling prevents cracking.

Refrigerate, still in the pan, for 5-6 hours or overnight, until completely firm.

Whip the heavy cream, powdered sugar, molasses, cinnamon, and nutmeg to stiff peaks. In a separate bowl beat the cream cheese smooth, then fold in the whipped cream in two additions.

With the cheesecake still in the pan, spread the mousse evenly over the top. Refrigerate 1-2 hours until firm, then remove the springform sides.

Whip the remaining cream, powdered sugar, cinnamon, and vanilla to stiff peaks. Pipe around the top edge, decorate if desired, and keep refrigerated until serving.