Mix the mascarpone with sparkling mineral water and Greek goat yoghurt. Add lemon zest, lemon juice and stevia. Mix energetically using a whisk or a hand mixer
Slice the strawberries and add half of them in the bottom of a serving glass
Add one part of the yoghurt mixture on top of strawberries. Repeat twice
Place in the freezer for 40 minutes
Before serving, decorate with a few slices of strawberry, fresh mint leaf or lemon zest