Preheat your oven to 350°F. Place six (four ounce) ramekins in a baking dish or roasting pan and set aside.
In a saucepan, heat the heavy cream over medium-low heat until it reaches a gentle simmer.
In a medium-sized heat-proof bowl, whisk together the egg yolks and ¼ cup of granulated sugar until it's pale yellow.
Add the pumpkin puree, maple syrup, vanilla extract, and pumpkin pie spice to the egg yolk mixture. Whisk to combine.
Slowly (and carefully) pour the hot heavy cream into the pumpkin mixture while whisking constantly.
Strain the custard through a fine mesh sieve to remove any scrambled egg and then divide it evenly between the ramekins.
Fill the baking dish with enough water so that it is halfway up the ramekins.
Bake for 45-50 minutes, or until the custard is set around the edges and just barely jiggly in the center. Remove the custards from the oven and let the ramekins cool to room temperature.
When the ramekins are cool enough to handle, remove them from the water bath, wrap them in plastic, and place them in the fridge to chill for at least 4 hours (or up to overnight).
Just before serving, sprinkle the top of each ramekin evenly with granulated sugar. Use a kitchen torch to carefully melt and caramelize the sugar until it turns golden brown and forms a crispy crust.
Enjoy immediately.