Place a thin, clean cotton kitchen towel in the bottom of a wide saucepan or deep skillet. Set your 2 ramekins on top. Make sure the towel lies completely inside the pan.

Bring enough water to a boil in a kettle. You'll use this for the stovetop water bath.

Gradually whisk in the heavy cream, milk and vanilla until smooth.

If you used ground vanilla powder, stir the mixture because the seeds go to the bottom. Then pour the mixture through a fine-mesh sieve into a jug. This should remove any bits of egg and give you a smoother custard.

Pour the hot water carefully into the pan around the ramekins. Aim for the water to come roughly halfway to two-thirds of the way up the sides of the ramekins.

Cover the pan with a lid and place it over low to medium-low heat. Keep the water at a very gentle simmer. Start timing when the water begins to simmer and cook for about 20–30 minutes, checking at around 20 minutes.

The custards are ready when the centers wobble gently when you tap the sides of the ramekins with a wooden spoon, but no longer look liquid. If using an instant-read thermometer, the center should read 171–176°F (77–80°C). Cooking time can vary depending on your ramekins and stovetop.

Carefully remove the ramekins from the hot-water bath and place them on a wire rack. Use oven mitts or sturdy kitchen tongs to carefully remove the hot ramekins. Remove the foil and let them cool at room temperature. Then loosely cover them with plastic wrap and refrigerate for at least 4 hours or overnight, so custard sets.

Blot the surface gently with a paper towel.

Sprinkle a thin, even layer of granulated or superfine sugar over the top. Gently shake the ramekin so sugar spreads evenly across the surface. Caramelize with a kitchen torch until melted and golden. Let the caramel harden. Wait about 5 minutes, then serve.