Prep 1 hr
Cook 40 mins
To ensure the custards cook gently and gradually, place the ramekins in a baking pan lined with a kitchen towel and partially fill the pan with hot water (known as a water bath). This helps insulate the delicate custards from the heat.
- Preheat an oven to 300°F.
- Line a shallow baking pan with a kitchen towel.
- Have a pot of boiling water ready.
- In a small saucepan over medium-high heat, bring the lemon juice to a boil.
- Reduce the heat to medium-low and simmer until the juice is reduced to about 1 tablespoon, 3 to 5 minutes.
- In another saucepan over medium heat, combine the cream, lemon zest and the 1/2 cup sugar.
- Cook, stirring occasionally, until steam rises, 2 to 3 minutes.
- Remove the pan from the heat and let stand for 15 minutes.
- In a bowl, whisk together the vanilla and egg yolks until smooth and combined.
- Slowly add the cream mixture, whisking constantly, then stir in the reduced lemon juice.
- Strain the mixture through a fine-mesh sieve set over a bowl and divide among six 3 1/2 ounce ramekins.
- Place the ramekins in the prepared baking pan and add boiling water to fill the pan halfway up the sides of the ramekins.
- Cover the pan loosely with aluminum foil and bake until the custards are just set, about 40 minutes.
- Remove the ramekins from the pan and transfer to a wire rack.
- Cool the custards to room temperature, about 1 1/2 hours, then refrigerate for 3 hours.
- Sprinkle 1 teaspoon sugar evenly over the surface of each custard.
- Using a kitchen torch according to the manufacturer’s instructions, move the flame continuously in small circles over the surface until the sugar melts and lightly browns.
- Serve immediately.