Preheat oven to 325°F (165°C). Wrap the outside bottom and sides of a 9-inch springform pan tightly with 2 layers of heavy-duty aluminum foil to create a waterproof barrier.

In a medium bowl, combine graham cracker crumbs, sugar, cinnamon, and melted butter. Press firmly into the bottom and slightly up the sides of the prepared springform pan. Bake for 10 minutes, then cool on a wire rack.

In a large bowl using a stand mixer fitted with paddle attachment or hand mixer on medium-low speed, beat cream cheese, granulated sugar, and brown sugar until completely smooth and lump-free (about 2 minutes). Do not overmix.

Add sour cream, vanilla extract, and flour. Beat on low speed until combined. Add eggs one at a time, mixing on low speed just until each yolk disappears. Do not whip air into the batter.

Pour batter into crust. Place springform pan inside a large roasting pan. Pour boiling water into roasting pan until it reaches halfway up the sides of the springform pan (water bath).

Bake at 325°F (165°C) for 55 to 65 minutes, until edges are set and center has a slight gentle wobble. Turn off oven, crack door open 1 inch, and let cheesecake cool in the turned-off oven for 1 full hour to prevent cracking.

Remove from water bath, unwrap foil, run a thin knife gently around edges, and cool to room temperature on a wire rack. Chill uncovered in refrigerator for at least 6 hours (preferably overnight).

Make topping: In a medium saucepan over medium heat, melt butter, brown sugar, and maple syrup. Bring to a gentle boil, stirring constantly for 3 minutes. Stir in heavy cream, cinnamon, salt, and vanilla. Simmer 1 more minute until thick and glossy.

Remove sauce from heat and fold in roasted pecans. Let cool for 15-20 minutes until warm and pourable but not piping hot. Pour evenly over the chilled cheesecake, slice with a warm sharp knife, and serve!