Butter the molds you’re using with the room temperature butter and refrigerate them for 15 minutes.

Remove from the refrigerator, butter the molds a second time, and return them to the refrigerator.

Preheat the oven to 400ºF (200ºC).

In a medium saucepan, warm the cream, butter, and vanilla over medium heat, stirring gently with a whisk until the butter is melted and the cream is lightly simmering.

Remove from heat and add the chocolate, stirring it gently to submerge it. Let it sit for about a minute, then stir with the whisk until the chocolate is melted and the mixture is smooth.

In the bowl of a stand mixer fitted with the whip, or by hand in a large bowl with a whisk, whip the whites until they start to hold their shape.

Whip in the sugar until the egg whites hold soft peaks.

Add a small amount of the egg whites to the chocolate mixture, about the size of a golf ball, then stir with the whisk until emulsified.

Scrape the chocolate mixture into the beaten egg whites and fold until they’re completely incorporated and no streaks of white are visible.

Divide the mixture into the buttered ramekins, being careful to keep the rims of the ramekins or soufflé dishes clean.

Set the ramekins on a baking sheet and bake until the soufflés are fully risen, but still jiggly when you nudge them.

They should feel barely set when you gently touch the center.

At the restaurant, the soufflés are baked for 6 to 8 minutes. At home, mine took 8 to 10 minutes in the smaller ramekins, 11 to 12 minutes in the larger ones.

Serve the soufflés warm from the oven. You can dust them with powdered sugar.