Prep the crust: Preheat the oven to 350°F. Line a spring form pan with parchment paper, set aside.
In a blender or food processor, add the gingersnap cookies and pulse until mostly broken then run on high until the mixture is a fine crumb. Transfer to a large bowl and drizzle with melted butter while stirring the crumbs with a fork until there are no longer dry spots of crumb.
Pour the buttered gingersnap crumbs into the prepared springform pan and lightly even out with a fork. Using the flat bottom side of a measuring cup or your hand, press down on the crumbs to form the crust starting on the bottom of the pain and working your way up the sides.
Bake the crust for 7 to 8 minutes. Remove from the oven and let the crust cool completely be filling with batter. Place the pan in the freezer to cool faster if needed.
Prep the filling: In a standing mixer or a large bowl with a hand mixer, beat the softened cream cheese until creamy about 2 minutes.
Beat the sugar into the cream cheese until fully incorporated, 2 minutes, scraping down the sides and bottom of the bowl.
On low speed, add the vanilla, molasses, spices and corn starch. Add the eggs, one at a time. Raise the speed to medium and mix until the ingredients are well incorporated incorporated, about 1 minute.
Pour the batter into the cooled crust in a wrapped springform pan (see notes) and place the wrapped springform pan directly in a larger, deep sided pan. Fill 1 to 1 ½″ up the spring form pan with water. Bake for 1 hour in the water bath. After 1 hour, shut off the oven and without opening the door let rest for 1 hour more.
After resting, remove from the water bath and remove the foil and wrap. Chill overnight in the refrigerator.
Make the meringue: Before serving, top the cheesecake with the meringue. Check your bowl to make sure it is completely clean and grease free. In a standing mixer with whisk attachment or with a hand mixer, add the egg whites, cream of tartar and salt.
Stir on low speed until the mixture is foamy, about 2 minutes, then increase the speed to high.
Gradually add the sugar, about 1 tablespoon at a time. Once all the sugar is incorporated, add the vanilla and continue to beat until the meringue is thick, shiny, and forms 'stiff peaks' on the end of the whisk attachment when taken out of the meringue.
Scoop the meringue on to the top of the cheesecake, swirling with the backside of a spoon. Use a kitchen torch to toast the meringue. Serve immediately or return to the fridge to chill before serving.