Preheat and Infuse:

1. Preheat your oven to 325°F (163°C).
2. In a small saucepan, heat the heavy cream with the split vanilla bean (or set aside the extract if using) over medium heat until it just begins to simmer. Remove from heat and let infuse for 10 minutes.

Whisk Custard Base:

1. In a mixing bowl, vigorously whisk together the egg yolks, 1/2 cup granulated sugar, and a pinch of salt until the mixture is smooth and slightly pale.

Temper and Strain:

1. Slowly drizzle the warm cream into the egg mixture while continuously whisking to temper the eggs.
2. If using vanilla extract, stir it in at this point.
3. Strain the custard through a fine sieve into a clean bowl to remove any solids.

Fill Ramekins and Bake:

1. Divide the strained custard evenly among the 4 prepared ramekins.
2. Place the ramekins in a baking dish and carefully pour boiling water into the dish until it reaches halfway up the sides of the ramekins.
3. Bake for 35–40 minutes, or until the custard is set around the edges but still slightly wobbly in the center.

Chill:

1. Remove the ramekins from the water bath and let them cool to room temperature.
2. Cover and refrigerate for at least 2 hours (or overnight) to fully set.

Caramelize the Top:

1. Just before serving, sprinkle an even, thin layer of granulated sugar over each custard.
2. Use a kitchen torch to melt and caramelize the sugar until it forms a crisp, golden crust. Alternatively, place the ramekins under a broiler for 2–3 minutes, watching closely to prevent burning.

Serve:

1. Allow the caramelized sugar to harden for a minute before serving. Enjoy your luxurious crème brûlée immediately, optionally garnished with fresh berries or a mint leaf.