Combine the pumpkin, brown sugar, cinnamon, nutmeg and salt in a bowl, mixing well. Add the eggs and heavy cream. Beat until smooth using a rotary or electric mixer. Stir in the mincemeat and pour into the unbaked pie shell. Bake in a preheated 220ºC . oven for 35 minutes or until the filling is set. Cool slightly on a wire rack and serve warm.