Chocolate Soufflés with Quick Chocolate-Coffee Sauce

INGREDIENTS

4 tbsp

unsalted butter, divided use

2 tbsp

unsweetened cocoa powder

170 g

70% bittersweet chocolate, chopped into chunks

1 tsp

vanilla extract

large eggs, separated

4 tbsp

granulated sugar

salt

cream of tartar

142 milliliters

heavy cream

1/8 cup

sugar

100 g

70% bittersweet chocolate, chopped into chunks

2 tbsp

unsalted butter

1 tsp

coffee or espresso powder