Blueberry key lime pie

1. 1. Set the oven to 150°C/gas 1. Roll out the pastry to line a 25cm tart tin and sprinkle the base with the grated zest of 2 of the limes. Bake the pastry blind and leave to cool.
2. Mix together the lime juice and remaining zest, the condensed milk, egg yolks, softened butter and double cream. Pour this mixture into the tart shell, place in the oven and cook for about 30-40 minutes, until set.
3. While the tart is cooking, make the Amaretto crème fraîche. Pour the Amaretto into a saucepan, slowly bring to the boil then remove from the heat. Spoon the crème fraîche into a bowl and pour in the Amaretto, mix well with the sugar and place in the fridge until needed.
4. When you are ready to serve, mix the blueberries with the sugar and add a squeeze of lime. Spoon them over the top of the pie and serve each slice with a dollop of Amaretto crème fraîche.