Blend strawberries and sugar in a food processor for 3-4 min at high speed. Whip egg whites and sugar to a stiff meringue. Fold the strawberries and lemon juice into the meringue. Serve right away or keep very cool.
Tip: its important that the egg whites, bowl and utensils all be the same temperature to get good, stiff peaks. Also, to avoid salmonella risk, do not cheat and use unpasteurized eggs.