Pour heavy whipping cream and 1 tablespoon sweetener into a saucepan over medium heat. Whisk constantly until it starts to simmer. Remove from heat; add yolk mixture slowly, whisking constantly, until well combined. Divide evenly between 4 ramekins and place them in a glass baking dish; pour in enough boiling water to come 1 inch up the sides of the ramekins.
Bake in the preheated oven on the middle rack until set, about 30 minutes.
Sprinkle 1 tablespoon sweetener over each creme brulee. Use a culinary torch to heat sweetener until melted and golden.