Raspberry Rhubarb Lattice Pie

Preheat the oven to 350 degrees.

Separate one-third of the pastry and refrigerate it, well wrapped, until ready to use. Roll out the remaining two-thirds for the bottom crust. Fit it into a pie plate and chill.

Put the raspberries and rhubarb in a large mixing bowl and sprinkle with the sugar, flour, and lemon juice. Toss very gently, so as not to break the raspberries. Spoon the filling into the pie shell and dot with butter. Refrigerate while you prepare the lattice top.

Roll out the pastry for the lattice and cut it into 1/2-inch strips. Weave the strips together over the filling, and place an extra strip or two along the edge, where the bottom crust joins the lattice top press this strip with the tines of a fork to seal well. In a small dish combine the egg and the heavy cream and stir quickly with a fork to blend thoroughly. Brush the lattice and all pastry edges with the glaze, and place the pie on a large parchment-lined baking sheet (to protect the oven from dripping fruit juices).

Bake for about 1 1/2 hours, until the pastry is golden brown and the juices in the center of the pie are bubbling. Let cool on a rack before serving.

Note If you are using frozen fruit, be sure it is completely thawed and well drained.