In a saucepan, bring the milk to a boil with the cinnamon stick and lemon zest. Cover the saucepan with plastic wrap and let it steep for 5 minutes to keep the flavors in.

In a mixing bowl, dissolve the cornstarch in a little hot milk, then add the egg yolks and sugar. Mix well.

Pour this mixture into the saucepan over low heat, stirring constantly until the cream thickens.

Pour the cream into ramekins and refrigerate for a few hours.

Before serving, sprinkle a thin layer of light brown sugar (or regular sugar if needed) on top and caramelize it with a kitchen torch.

If you don't have a torch, caramelize the sugar under the oven broiler.