To prepare the Lemon Curd: In a small saucepan combine egg yolks, sugar, lemon juice, and lemon zest. Cook slowly over medium low heat for 10 minutes stirring constantly until the mixture thickens enough to coat the back of a wooden spoon.

Remove from heat and stir in butter a few pieces at a time until completely smooth. Cover with plastic wrap and chill completely in the fridge.

To prepare the Sour Cream Pastry, cut butter into the flour and salt with a food processor or pastry blender until mixture resembles a coarse meal. You should still see small pieces of butter in the mix. Stir in the sour cream to form a dough. Form dough into two rectangles, wrap in plastic and rest in the fridge for 20 minutes.

Roll out dough to about 1/4-inch thickness and cut into 4-inch squares.

Spoon a heaping teaspoon of lemon curd into the centre of each pastry square and fold over. Press edges down firmly with the tips of your fingers to seal. Place turnovers on a parchment- lined baking sheet.

Preheat oven to 375F (191C) and bake for 20-25 minutes until light golden brown. Cool for at least 20 minutes before serving.