Preheat oven to 325°F, in a food processor add graham crackers and sugar blitz on high until crumbles form. Then cut on low and slowly drizzle in 4 tablespoons of butter. Crust should hold together when squeezed in hand. Use remaining butter to butter the bottom of a 10-inch springform pan. Press mixture evenly and firmly into the bottom and sides of pan. Place on a baking sheet and pop in the oven for 13 minutes. Let crust cool for 10 minutes before pouring in filling.

While crust bakes make sweet potato base, in a medium bowl with a hand mixer on low speed, combine sweet potato puree, flour, melted butter, cinnamon, nutmeg, ginger and ¼ teaspoon salt, until smooth.

Cut oven to 425°F. In a stand mixer bowl add the cream cheese, brown sugar and salt, using a paddle attachment, mix on low speed for 1 minute. Add the sour cream and orange zest, mix on low for 1 minute, scrape down sides of bowl. Add vanilla extract and 2 eggs, mix on low for 1 minute, scrape down sides of bowl. Add 2 eggs at a time, mix on medium for 1 minute. Mixture will be smooth and loose when finished.

Stir ½ cup of the cream cheese mixture into the sweet potato base. Pour half of the cream cheese into the pan. Take spoonfuls of the sweet potato base and drop over cream cheese. Repeat again, then use a butter knife to swirl the sweet potato base; avoid going too deep, and scraping the crust.

Bake for 10 minutes, then cut the heat down to 200°F and bake for 1 hour and 20 minutes until the center of the cheesecake jiggles slightly or registers to 150°F with an instant-read thermometer.

Remove from oven and let cheesecake cool for 5 minutes, run a knife around the outside of the cheesecake to release it. Cool at room temperature for 3 hours. Cover with plastic wrap and place in refrigerator overnight.

In a small pot over medium heat melt butter, then stir in brown sugar, maple syrup, pecans, vanilla and salt, cook for 3-5 minutes until the sauce thick with a syrup consistency. Set aside to cool.

The next day sit cheesecake out at room temperature for 15 minutes before you release it. Spoon butter pecan sauce around the edge of cheesecake.