Canadian Butter Tarts

In a large bowl, beat the eggs, then combine them with the muscovado sugar, raisins, vanilla extract, butter, and single cream. Pour this mixture into a pan and stir continuously for 3-4 minutes, or until the butter has melted, the mixture begins to bubble, and it starts to thicken. You're looking for a consistency that's thick enough to coat the back of a wooden spoon; be careful not to overcook it, and keep stirring to prevent burning. Remove the pan from the heat and stir in the walnuts.

Spoon the cooked filling into the unbaked pastry shells, filling them just to the level of the pastry. Bake for 15-18 minutes, until the filling is set and the pastry is pale golden. Let the tarts cool in their tins for a few minutes before carefully transferring them to a wire rack. Serve them warm or at room temperature.