Yield: 2 cakes
2 tablespoons unsalted butter, softened
1/4 cup granulated sugar
1 large egg
1/2 teaspoon pure vanilla extract
1 tablespoon store-bought caramel sauce
2 tablespoons milk
6 tablespoons self-rising flour
1/2 teaspoon fleur de sel or other high-quality sea salt, divided
4 caramel candies, preferably salted
1. In a large mug, whisk together the butter and sugar with a fork. Stir in the egg, vanilla, caramel sauce and milk. Add the flour and 1/4 teaspoon of the fleur de sel. Beat the batter until smooth.
2. Divide the batter between two mugs. Top each mug with a pinch of the remaining fleur de sel. Microwave separately for 30 seconds each.
3. Top each mug with two caramel candies. Continue cooking 1 to 1 1/2 minutes more (each separately) until risen and firm.