Bilberry pie

Crust:

2.5 dl / 1 cup water or milk
25 g / 0.9 oz yeast
1 tsp. salt
0.5 dl / 3½ tbsp. sugar
1 egg
7–8 dl / 2¾ cups wheat flour
75 g / 2.5 fl oz margarine

Filling:

1.5 l / 5¼ cups frozen or fresh bilberries; slightly mashed
Approx. 1 dl / ½ cup potato flour
2 dl / ¾ cup sugar

Dissolve the yeast in lukewarm water or milk. Add the salt, sugar and egg. Knead the flour into a dough. Mix the dough well, either by hand or using a mixer. Pour the melted margarine into the dough. Knead the dough until it is solid. Roll the dough into a baking tray (Use the remaining dough as strips to form a lattice on top of the filling.) Mix the ingredients for the filling together. Spread the filling evenly onto the dough in the baking tray. Then add the strips of dough to form a lattice. Bake at 175–200 °C for about 30 minutes.