Place flour, salt, butter and lard in food processor. Pulse a few times and slowly add enough ice water until dough forms. Remove from processor bowl and pat out on a floured board. Cut into two pieces and wrap each in plastic wrap. Chill in frig for 2 hours.

At one and a half hours, place rhubarb with brown and granulated sugar into a large bowl. Stir well and let sit while crust continues to chill.

Preheat oven to 400. Roll out pie crust for bottom of pie. In bowl with rhubarb stir in strawberries, lemon zest, vanilla, salt and cornstarch.

Pour fruit into pie crust, dot with better cubes and top with lattice or regular crust.

Beat egg with milk and brush on top of pie. Top with extra sugar. Bake on baking sheet for 20 minutes.

Turn heat down to 350 and now bake for additional 25 minutes.

Let pie cool for at least 2 hours.