Chocolate Salted Caramel Cupcakes

INGREDIENTS

• :
• ½ cup plus 1 tablespoon Dutch-process cocoa powder
• ½ cup plus 1 tablespoon hot water
• 2¼ cups all-purpose flour
• ¾ teaspoon baking soda
• ¾ teaspoon baking powder
• ½ teaspoon salt
• 1 cup plus 1 tablespoon unsalted butter, at room temperature
• 1 & 2/3 cups granulated sugar
• 3 eggs
• 1 tablespoon vanilla extract
• ¾ cup sour cream
• 1 cup unsalted butter, at room temperature
• 8 ounces cream cheese, at room temperature
• ½ cup
• 4 cups powdered sugar
• Salted Caramel Sauce
• Fleur de Sel (or other flaky sea salt)