Meanwhile, beat eggs, vanilla, and salt with an electric mixer until light in color. Gradually add in the sugar and continue beating for 5-10 minutes until mixture is thick, pale, and drops down in the bowl like ribbons.
Sift a third of the flour into the egg mixture, folding it in after each addition.
Take about 1/2 cup egg mixture and mix it with the cooled butter. (This is important for adequately mixing in the butter into the batter.) Mix this tempered butter into the rest of the batter, folding it in until combined.
Cover batter with plastic wrap and chill in fridge for 60-90 minutes.
Preheat oven to 350 degrees F. Brush molds with melted butter and then use a cookie scoop to drop the batter into the wells. No need to spread. Bake for 11-13 minutes or until edges start to lightly brown and tops spring back when gently pressed with your fingertip.
Immediately remove from pan onto a cooling rack with the bottom ruffle edge up. Sprinkle with powdered sugar and serve.
For the Glaze:
Mix all glaze ingredients together and dip warm Madeleines in.