Preheat the oven to 400° F.
Put all the filling ingredients except the blueberries together into a bowl and mix. Add the blueberries and mix well, coating the blueberries evenly. Set aside.
Butter four, 4 inch tart or pie tins
Take out one of the pie crusts Cut into four equal pieces. Press each square into the pie tin - pressing against the bottom and sides. Cut or press off any excess on the rims. Put them into the refrigerator to chill.
Take out the second pie crust. Slice 8-10 half inch strips for a lattice top. Put the strips into the fridge.
Take out the pie shells from the refrigerator. Place the mini pies on a baking sheet. Spoon the blueberry mixture into the pie shell. Take the pastry strips out of the refrigerator and place two across the pie. Take another two pieces and weave in and out creating a lattice. Cut the excess from the sides and press the ends to the edges.
Brush the top with egg wash and sprinkle with sugar.
Place the mini pies in the middle of the pan. Line the baking sheet with parchment if desired, for faster clean up later as the blueberry juices may spill onto the pan. Bake in the middle of the over for about 20 minutes or until the filling is bubbly and the crust is golden brown.
Allow to rest in the oven with the door closed for about five minutes before cooling on a rack.