01 -
Turn your oven to 392°F (200°C) and let it heat up. Wrap the sweet potatoes in foil, then roast them for about 1 hour and 10 minutes.
02 -
While the potatoes are roasting, stir together the sugar, cornstarch, and salt in a pot. Pour in the milk and whisk until it looks smooth. Heat this over medium, whisking continuously until it thickens.
03 -
In a small dish, slightly beat the egg yolks. Slowly pour around 1/4 cup of the hot milk mix into the yolks, stirring to combine. Transfer the yolk mixture back into the pot.
04 -
Stir on medium heat for another 2 minutes, or until it's thickened up. Take the pot off the stove, drop in the butter and vanilla, and whisk until smooth.
05 -
Spoon the custard into a bowl. Lay plastic wrap directly on the surface to stop skin from forming. Let it cool down at room temperature.
06 -
After letting the sweet potatoes cool for 10 minutes, slice off the tops. Scoop out about one-third of the flesh, then spoon in the custard evenly across each potato.
07 -
Sprinkle roughly 1 tsp of sugar over the top of each filled potato. Use a kitchen torch to melt the sugar until it's bubbly and golden. Let it set before serving.