Velvety French Macarons

Ingredients

• 2 pounds unsalted butter, at room temperature
• 1 tablespoon vanilla extract
• 1 pound granulated sugar
• 12 ounces egg whites, divided
• 1/2 cup corn syrup
• 170 grams egg yolks
• 1 cup granulated sugar
• 1 pound almond flour
• 1/2 teaspoon salt
• 1 pound confectioners sugar
• 4 ounces water