Preheat the oven to 375°F (190°C). Line a large baking pan with parchment paper and place sweet potatoes onto the pan. Take a fork and poke holes into the top of each sweet potato. Place into the oven and bake for 45-55 minutes, until soft if poked with a fork. Set aside until cool enough to handle.

Press down with your hands on top of each sweet potato to slightly flatten the top. Cut the top piece of sweet potato skin off and remove. Using a spoon, carefully scoop out most of the sweet potato flesh, leaving about ½” of flesh all the way around - like a bowl. Measure out ½ cup of sweet potato from the excess and mash with a fork or blend into a puree. If you accidentally make a hole, patch it up with some mashed sweet potato flesh and press it into shape. Set aside.

In a large pitcher or measuring cup, combine egg yolks, sugar, and sweet potato puree. Stir together until smooth.

Add salt, cinnamon, vanilla extract, whipping cream, and milk. Stir to combine.

Pour the crème brûlée mixture into the hollowed out sweet potatoes. If you have extra mixture, you can bake it in a ramekin (see below instructions for how to bake crème brûlée in a ramekin).

Bake at 340°F (170°C) for 20-25 minutes, until the crème brûlée is set on edges and still wiggly in the center. This may take more or less time, depending on the size of the sweet potato. Let cool completely and refrigerate until set - 2 to 4 hours or overnight.

Bake one sweet potato in an oven preheated to 375°F (190°C). Bake until soft and squishy, about 45 to 55 minutes. Let cool and mash with a fork or a blender.

In a large pitcher or measuring cup, combine egg yolks and sugar. Stir together until smooth.

Add salt, cinnamon, vanilla extract, sweet potato puree, whipping cream, and milk. Stir to combine.

Pour the crème brûlée mixture into 4-6 ramekins. Place ramekins into a larger baking pan with tall edges. Pour boiling water into the baking pan, around the ramekins.

Bake at 340°F (170°C) for 18-22 minutes, until the crème brûlée is set on edges and still wiggly in the center. Let cool completely and refrigerate until set - 2 to 4 hours or overnight.

Sprinkle one to two teaspoons of granulated sugar on top of each crème brûlée and spread to cover liberally.

Just before serving, using a kitchen torch, carefully melt and burn the top of the crème brûlées. Be careful not to light the sweet potato skins. You can also use the broil setting in your oven to do this - I don’t recommend this if you made the crème brûlée inside of the sweet potatoes because the skin might light on fire. The broil oven function will work on ramekins. Let the sugar set and serve immediately!