Divide the crushed biscuits between 4 glasses. Mix the soft cheese, yogurt, sugar and lemon zest together. Spoon into the glasses over the top of the biscuit base.
In a medium pan, warm the water with the sugar over a gentle heat, until the sugar dissolves. Turn up the heat and boil for 2 minutes. Reduce to a simmer, add the cherries and cook for a further 10 minutes, until the juice is syrupy and the cherries are soft. Remove from the heat and let cool
Spoon a large tablespoon of cherries into the top of each glass. Chill until ready to serve.