Preheat oven to 350°F. Generously butter and flour pan for large Madeleine's (about 3 x 1¼ inches). Using electric mixer, beat eggs and ⅔ cup sugar in large bowl just to blend. Beat in vanilla, lemon peel and salt. Add flour and Baking Soda; beat just until blended. Gradually add cooled melted butter in steady stream, beating just until blended.
Spoon 1 tablespoon batter into each indentation in pan. Bake until puffed and brown, about 15 minutes. Cool 5 minutes. Gently remove from pan.
Makes about 20
Recipe by Sugar and Spice at https://kathleenssugarandspice.com/2010/09/30/cest-magnifique-madeleine-cookie-recipe/