Preheat oven to 300 F. Spray a 10-inch springform pan with baking spray. If it doesn't contain flour, dust a little over the spray. Line the bottom of the pan with parchment paper. Then, spray the paper as well.
Wrap the bottom of the pan with foil. It should come all the way up the sides and be crimped tightly. This is so that water doesn't seep in, so I always add a double layer just to be safe!
In a medium bowl, combine graham cracker crumbs, pecans, toffee bits, and melted butter. Press the mixture into the bottom of the prepared pan.
In a large bowl, beat cream cheese and sugar with a mixer on medium speed until smooth and creamy.
Add eggs, one at a time, beating just until combined after each one. Then add sour cream, melted white chocolate, and vanilla. Beat to combine.
Reserve 1 ½ cups of the batter. Pour remaining batter into the prepared pan.
In a medium bowl, combine 1 cup of the reserved batter, pumpkin, and spices. Pour evenly over the batter in the pan.
Drop remaining ½ cup of reserved batter by tablespoons over the pumpkin batter. Using the edge of a knife, create a swirl pattern in the batter.
Place cheesecake in a roasting pan, and place roasting pan in the preheated oven. Fill roasting pan with enough water to come halfway up the sides of the springform pan.
Bake for 90 minutes. Turn oven off, leaving the cheescake in the oven for 2 more hours. Don't open the door during this time. Remove cheesecake from oven and refrigerate for 24 hours.
Carefully run a knife around the edges of the cheesecake to loosen the sides. Remove from pan and serve.