Method

• Roast the Sweet Potatoes: Preheat oven to 400°F (200°C). Prick the sweet potatoes all over with a fork. Wrap each potato individually in aluminum foil. Roast for 45-60 minutes, or until tender when pierced with a fork.
  
  
• Make the Crème Brûlée: In a saucepan, whisk together heavy cream, 1/4 cup granulated sugar, and cornstarch. Bring to a simmer over medium heat, stirring constantly, until the mixture thickens. Remove from heat and let cool slightly.
  
  
• Temper the Egg Yolks: In a separate bowl, whisk together egg yolks. Gradually whisk in a small amount of the warm cream mixture into the egg yolks, then pour the egg yolk mixture back into the saucepan with the remaining cream.
  
  
• Cook the Custard: Cook over low heat, stirring constantly, until the custard thickens. Remove from heat and stir in vanilla extract.
  
  
• Assemble: Once the sweet potatoes are cool enough to handle, cut them in half lengthwise. Scoop out a small amount of the flesh from each half, creating a cavity.
  
  
• Fill and Bake: Fill each cavity with the warm custard. Bake in a preheated oven at 325°F (165°C) for 15-20 minutes, or until the custard is set.
  
  
• Caramelize the Sugar: Sprinkle the surface of each custard with granulated sugar. Use a kitchen torch to caramelize the sugar until golden brown.
  
  
• Serve: Serve immediately and enjoy the delightful combination of sweet potato and creamy custard.