Preheat oven to 325 degrees. Line six 6-oz. ramekins or custard cups into a deep baking pan. Boil together heavy cream and milk along with half of the sugar and the cinnamon stick. Blend egg yolks with the remaining sugar. Gradually blend one-third of the hot cream to the yolks, whisking constantly. Add the remaining hot cream and stir. Combine spices and pumpkin purée. Remove hot cream mixture from heat, and slowly whisk in purées and spices. Strain the custard through a finemesh sieve into a clean container. Carefully ladle or pour the custard into the prepared ramekins, filling those three-fourths full. Place the baking pan on a pulled-out oven rack. Add enough boiling water to come halfway up the sides of the ramekins. Carefully slide in the rack and bake for roughly 20–25 minutes, until the edges have set and a nickel-sized spot in the center jiggles slightly when custard is shaken. Remove the ramekins from the water bath. Let the custards cool on a rack for 30 minutes, wrap individually and refrigerate for at least 3 hours or up to 3 days before finishing with the brûlée layer. To finish, evenly coat the top of each custard with a thin layer of sugar, about 1 Tbsp. Use a kitchen blowtorch or the broiler to evenly melt and caramelize the sugar. Serve immediately.