In a large bowl, gently toss together the raspberries, sugar, flour, lemon juice and nutmeg. Set aside.
Roll out half of the pastry and fit it inside a 9 inch pie plate, trimming off the excess pastry.
Place the raspberry mixture inside the pie crust.
Lightly wet the edge of the crust with a bit of water.
Roll out the other half of the pastry and set it over top of the berries, or cut it into one inch strips and weave the strips into a lattice top over the berries.
Crimp the edges to seal them. If you are using a full crust, cut slits in the top to vent the pie.
Whisk together the egg and water and brush it lightly over top of the pastry.
Sprinkle with a bit of extra sugar.
Place the pie on a baking sheet in case it bubbles over.
Bake for 15 minutes, then REDUCE THE HEAT to 375 degrees F and continue baking for another 35-40 minutes or until the crust is lightly browned and the filling is bubbling.
If the pastry is getting too brown and the filling isn’t bubbling yet, tent some foil over top to prevent more browning.
Allow the pie to cool completely before slicing so that the filling will firm up.