Classic Marshmallows, and Some Variations Recipe

Ingredients (10)

• ½ cup confectioners sugar
• ½ cup potato starch (or corn starch)
• 1 teaspoon butter
• 1 cup water, divided
• 2 cups granulated sugar
• Two ¼-ounce packets of unflavored powdered gelatin (about 5 teaspoons)
• 1 tablespoon vanilla extract (or other flavoring, see variations in note above)
• 3 large egg whites, at room temperature (see note on eggless marshmallows above
• pinch salt
• 1/8 teaspoon cream of tartar