The recipe for French macaroon shells is quite classic: icing sugar, egg whites and almond flour, much finer than almond flour due to grinding. If you have a nut allergy or just want to experiment with other types of flour, you might be inclined to simply substitute almond flour for another type of flour. But this simple exchange will inevitably lead to disaster. Macaroons are supposed to be made with almond flour for several reasons. The combination of almond flour with a firm meringue is ideal for the piping. The resulting texture when you bite into these cookies is soft, chewy, and melt-in-your-mouth. All-purpose flour just wouldn’t produce the same result.
Amanda Schlarbaum notes that although some people have tried making macaroons from other nut flours, the result isn’t the same either. “You can try another nut or experiment with seeds, like pumpkin or sunflower, but that won’t produce the traditional macaron in color or flavor.”
Be sure to opt for blanched almond flour, which does not contain the shells of the nuts. (The rinds are full of oil, which can mess up your recipe further.) Using blanched almond flour will help ensure a smooth texture for your macaroons.