Ingredients

1/4 cup sugar 

1/2 cup heavy cream 

4 tablespoons (1/2 stick) unsalted butter, cut into small pieces 

3 ounces semisweet chocolate chips 

1 ounce unsweetened chocolate, finely chopped 

1/2 teaspoon pure vanilla extract 

Pinch of coarse salt 

Preparation

In a small saucepan, bring sugar and heavy cream to a boil over medium-high. Cook, stirring often, until sugar dissolves, 2 minutes. Add butter and both chocolates, and stir until chocolates melt and sauce is smooth, 2 minutes. Stir in vanilla and salt.