25 soft caramel candies, such as Kraft Classic Caramels, unwrapped
1/4 cup heavy cream
1 cup all-purpose flour
1/2 teaspoon baking powder
1/2 teaspoon fine sea salt
1 1/4 cups granulated sugar
3/4 cup (1 1/2 sticks) unsalted butter, at room temperature
1 teaspoon vanilla extract
3 eggs, at room temperature
1/2 cup creamy peanut butter
1/2 cup (1 stick) unsalted butter, at room temperature
4 cups powdered sugar
1/4 cup whole milk, at room temperature