Prep the pan: Heat oven to 325°F (163°C). Wrap the outside of a 9-inch springform pan with two layers of heavy-duty foil. Lightly grease the inside.

Make the crust: Combine 2 cups graham cracker crumbs, 1/4 cup brown sugar, and 6 tablespoons melted butter. Press firmly into the bottom and 1 inch up the sides of the pan. Bake 8–10 minutes. Cool slightly.

Beat the base: In a large bowl, beat 32 ounces softened cream cheese with 1 cup granulated sugar and 1/4 cup light brown sugar until smooth and fluffy, about 2–3 minutes. Scrape the bowl.

Add pumpkin and sour cream: Mix in 1 cup pumpkin puree, 1/2 cup sour cream, and 2 teaspoons vanilla until smooth.

Spice and set: Add 1 tablespoon cornstarch, 1 1/2 teaspoons cinnamon, 1/2 teaspoon ginger, 1/4 teaspoon nutmeg, 1/8 teaspoon cloves, and 1/2 teaspoon kosher salt. Blend just until combined.

Finish with eggs: Beat in 4 eggs plus 1 yolk, one at a time, on low speed. Do not overmix; stop when just incorporated.

Assemble the bath: Pour filling into the crust. Place the pan in a large roasting pan. Pour hot water into the roasting pan to reach halfway up the springform.

Bake: Bake 70–85 minutes. The edges should be set and the center should jiggle slightly like Jell-O.

Cool slowly: Turn off the oven, crack the door, and let the cheesecake sit inside 1 hour. Remove from the bath, discard foil, and cool to room temp.

Chill: Cover and refrigerate at least 6 hours, preferably overnight, for the creamiest texture.

Serve: Release the springform ring. Slice with a hot, clean knife. Top with whipped cream, if desired.