Step 1 Adjust an oven rack to the middle position. Preheat the oven to 325F.
Step 2 Put the graham cracker crumbs and sugar in a medium bowl and whisk. Pour the melted butter over the top and stir with a spatula until combined. Press the mixture into a 9-inch springform pan and bake 10-12 minutes, or until the crust is golden. Remove from the oven and set aside to cool.
Step 3 Melt the white chocolate in a heatproof bowl set over a pan of boiling water, being careful not to let the water touch the bottom of the bowl, and stir constantly until just melted. Let the chocolate cool until the chocolate remains liquid but is cooled to room temperature, about 10 minutes.
Step 4 In a stand mixer fitted with a paddle, beat the cream cheese on high until smooth and creamy, about 3 minutes. Add the sugar, salt, and vanilla and beat on medium until light and smooth, about 3 minutes. Add the white chocolate and mix on low until just combined. Use a spatula to finish stirring the white chocolate into the cream cheese, making sure it is totally combined. Transfer the cream cheese mixture to a large bowl and set aside. Clean the mixing bowl if you have only one.
Step 5 In a stand mixer fitted with a whisk, beat the cream (in the clean bowl) on low for 30-45 seconds. Increase the speed to medium and continue beating 30-45 seconds. Increase the speed to high and continue beating until stiff peaks form, 30-60 seconds.
Step 6 With a rubber spatula, stir about one-third of the whipped cream into the cream cheese mixture and fold until completely combined. Add the remaining whipped cream and fold until combined and no streaks remain.
Step 7 Scrape the filling over the cooled crust and smooth the top with an offset spatula. Decorated the top with jam swirls (see below). Refrigerate the cheesecake until firm, about 4 hours or up to 1 day.
Step 8 For the jam swirls: Combine the jam and 1 tablespoon water in a small saucepan. Warm over low heat until the jam is loose. Let the mixture cool a bit. Drop the jam in circles over the top of the cheesecake and use a skewer or knife to drag it through the top of the cheesecake, making swirls.
