Wash the lemons and grate them dry. Halve 1 lemon and squeeze the juice. Heat lemon juice and sugar until the sugar is dissolved. Let the juice cool down
Cut the other lemon into very thin slices. Pluck the rose petals from the stem. Place the rose petals and lemon slices in a carafe and fill up with mineral water and lemon juice. Chill for about 30 minutes. If necessary, serve with additional ice cubes
Waiting time approx. 1 hour