In a bowl, sprinkle gelatine over water and let bloom. Meanwhile, combine milk, cream, sugar and vanilla in a saucepan and stirring constantly, bring to a gentle simmer. Add bloomed gelatine, stir well to dissolve and pour into containers. Put in fridge for at least four hours, preferably overnight.
Clean and cut strawberries, then add to a saucepan and cook over medium-low heat. Add sugar, depending on how sweet your strawberries are and how sweet you want your compote to be. Once thickened, remove from heat and allow to cool. Cook tapioca according to package instructions and add to cool compote. Pour over hardened panna cotta mixture and allow to cool before serving