Vanilla Bean Caramel Blondies

unsalted butter (1 stick), melted

large egg

light brown sugar, packed

vanilla extract

all-purpose flour

salt, or to taste

unsalted butter, melted (half of 1 stick)

light brown sugar, packed

tablespoons half-and-half or cream

tablespoon vanilla bean paste (1 tablespoon vanilla extract may be substituted)

confectioners’ sugar, sifted (must be sifted)

salt, optional