Preheat the oven to 350 degrees.
Mix graham cracker crumbs, brown sugar and melted butter until combined. Spread in a 9x13 baking dish and press evenly into the bottom of the pan.
Beat softened cream cheese and sugar until smooth. Add eggs and vanilla and pour over crust.
Whisk together the pumpkin, sweetened condensed milk, eggs, spices, and salt until smooth. Pour over cream filling.
Bake at 350 degrees for about 45 minutes, or until the center of the pumpkin filling is set and no longer jiggles.
Cool completely, then refrigerate for 4 hours or overnight before serving. Add a dollop of fresh whipped cream, if desired.
Store leftovers covered in the fridge.