Preheat the oven to 325F. In a medium mixing bowl add the egg yolks and 1/2 cup granulated sugar. Whisk for about 2 minutes, until light in color.
Whisk in the pumpkin puree and pumpkin pie spice until combined.
Add the heavy cream and vanilla extract to a medium saucepan over medium heat. Heat, stirring often, until the mixture reaches a simmer.
Slowly add ½ cup of the heavy cream mixture to the pumpkin egg mixture while whisking continually. While continuing to whisk, add the remaining heavy cream mixture to the eggs and whisk until combined. Pass the mixture through a fine mesh sieve to sift out any cooked egg pieces from the mixture.
Place the ramekins on a baking dish. I like to use a casserole dish but you can use any high sided baking dish that is oven safe. Fill the ramekins with the pumpkin mixture.
Add hot water to the baking dish, being sure it does not get into the ramekins, until the water reaches halfway up the sides of the ramekins.
Bake at 325F for 40-50 minutes, until the edges are set and the centers of the crème brûlée are still jiggly. Carefully remove the ramekins from the baking dish and place on a cooling rack to cool to room temperature. Once cool, place in the refrigerator to chill for at least 4 hours.
When ready to serve, add a teaspoon of granulated sugar to the top of each crème brûlée. Tilt the ramekin from side to side to spread the granulated sugar in an even layer on the surface.
Use a kitchen torch to caramelize the sugar. I find that it’s best to not get too close to the sugar or it will burn. Slow and steady will create a more even caramelization.
Serve immediately.