Separate egg whites from yolks, placing whites in a dry bowl.
Mix flour, salt, almond milk, and egg yolks in a large bowl until smooth. Avoid overmixing.
Whip egg whites with a mixer on medium speed, gradually adding sugar until stiff, glossy peaks form.
Fold a quarter of the whipped egg whites into the batter gently, then fold in the remaining whites in two batches, keeping the mixture uniform and airy.