In a small bowl, whisk together the cooled melted butter, eggs, almond extract, and sugar to combine. Add the milk and whisk until smooth. In a medium bowl, whisk together the salt, flour, and baking powder. Add the liquid ingredients to the dry and stir to combine, but do not overmix. Fold the blueberries into the batter with a spatula. Using a scoop, divide the batter amongst the 12 wells of a greased muffin tin. Sprinkle the tops with additional sugar and bake for 20-25 minutes, until the tops are golden brown and crackly and a toothpick inserted in the center of a muffin comes out clean.