Preheat the oven to 325 (F).
In a medium heatproof bowl, whisk together 1/2 cup granulated sugar and 5 egg yolks until well combined. Set aside.
In a medium sauce pot, combine 1 1/2 cups heavy cream, 1 cinnamon stick, a pinch of nutmeg and a pinch of salt. Split open 1 vanilla bean pod lengthwise and use the tip of a knife to scrape the vanilla beans into the cream mixture. Once you have "deseeded" the pod, add it to the sauce pot. Bring the mixture to a simmer over medium heat, whisking occasionally to prevent the cream from forming a skin.
Once the cream is simmering, remove from heat. Slowly whisk the hot cream mixture into the yolk mixture (from the 2nd step) through a fine mesh sieve until well combined.
Once the cream mixture is combined into the yolk mixture, whisk in 3/4 cup pumpkin puree until well combined.
Divide the mixture among 8 four-ounce ramekins and place in a large baking pan. Add boiling water to fill the pan halfway up the sides of the ramekins. Cover the pan loosely with aluminum foil and bake until the custards are just set, around 30 minutes. When the custards are done, the center should be a little bit jiggly but the edges should be set (see baker's notes). Transfer the ramekins onto a wire rack and let cool to room temperature. Cover each ramekin with plastic wrap and refrigerate for at least 4 hours, or up to 3 days.
Just before serving, prepare 1/2 cup granulated sugar by processing in a food processor. This will break up the sugar crystals and turn your sugar super fine.
Sprinkle 1 teaspoon of superfine sugar evenly over the surface of each custard. Use a chef's torch to move a flame continuously over the surface of the sugar until the sugar melts and lightly browns. Let rest for a minute to allow the sugar molten to harden, before serving immediately.