Place the chocolate chips in a small heat-proof bowl.

In a small saucepan, combine heavy cream and vanilla and heat on medium-low until small bubbles appear at the edges of the pan.

Pour the hot cream mixture over the chocolate chips.

Stir with a fork until the chocolate is melted and the mixture is smooth.

Crush the flaky sea salt with your fingers and stir into the chocolate mixture.

Cover the bowl until ready to serve (see Notes). The sauce can be made 2 days in advance. It keeps chilled for 2 weeks.

Before serving, heat in the microwave in 15 second increments, stirring in between, until warm (not hot) and easier to drizzle.