Cut strawberries in quarters (not the strawberry halves). Put quartered strawberries and sugar in a heavy pot and cook for a couple of minutes at medium heat, then cook at low heat for a few minutes covered until all the fruit juice is released. Uncover, add lemon juice, and cook for 5 minutes at medium low. Then let cool for a few minutes (not completely).

Combine gelatin and water and let gelatin bloom for 5 minutes. Stir the gelatin into the cooked strawberries while still hot, and let completely melt.

Puree the strawberry and gelatin mixture in a food processor. Pour out into a bowl, and cool the puree using an ice bath, stirring constantly until cold and thick.

Whip heavy cream to soft peaks. Set aside a couple of tablespoons of whipped cream for decoration, adding sweetener if you like. Add the cream to strawberry mixture and mix well. Pour into 4-6 serving cups equally. Chill for at least 4 hours.

Garnish with whipped cream and strawberry halves.