In a saucepan, over low heat, melt butter. Remove from heat. Stir in confectioner’s sugar and vanilla extract.
Add warm whole milk, 1 tbsp at a time, stirring constantly, until smooth and has consistency of thick syrup.
Pour or spread over dessert. Let set for 15-20min. Alternative recipe w/ less butter (tried on pumpkin cookies) Ingredients: whole milk 3 tbsp butter 1 tbsp confectioners’ sugar, sifted 2 cups vanilla extract 1½ tsp