Place lemon zest into a cool oven (120°C) and dehydrate until the zest become brittle and dry. Reserve zest until ready to use.
Place dried zest and sugar into Thermo bowl and mill 1 min/speed 10. Cool slightly. Repeat 1 min/speed 10. Cool, repeat.
Scrape down sides of bowl and remove sugar from bowl and set aside.
Preheat oven to 120°C and line a large baking tray with paper and set aside.
Place egg whites into clean, dry Thermo bowl. Whip 4 min/50°C/Butterfly/speed 3.
Slowly add 1 tsp lemon sugar at a time through hole in lid and whip 2 min/50°C/Butterfly/speed 3. The mixture will be runny. Spread it onto prepared tray and cook for 1 hour until well cooked, a little chewy in the centre but crunchy around the outside. Cool completely.
Line the base of a springform cake tin with paper.
Place cream into Thermo bowl. Whip 20-30sec/Butterfly/speed 4 or until very soft peaks form.
Add lemon butter and stir through 3 sec/speed 3. Remove Butterfly.
Break up meringue and add to bowl. With the aid of the spatula, incorporate 10 sec/speed 6.
Spread into prepared cake tin and freeze for a few hours.
Beautiful presentation can be achieved with shaped moulds or by making individual servings in ramekins or dariole moulds.
Serve with fresh berries.