PASTRY:

1.5 cups all-purpose (unsifted) flour
1 tablesp sugar
1/2 cup butter or margarine
1 large egg (beaten)
1 tablesp cider vinegar

FILLING:

2 lbs Rhubarb stalks
4 large granny smith apples
1.25 cups sugar
1/4 cup corn starch
1 teasp ground cinnamon
2 tablesp buter or margarine
1 tablesp lenom juice
Red food coloring (optional)

Pastry:

Mix flour and sugar.  Cut in butter with pastry blender until mixture resembles coarse crumbs.  Beat egg.  Add water to egg until mixture is 1/3 cup. Stir in vinegar.

Add 4 tablespoons egg mixture to flour mixture.  Mix lightly with a fork until pastry holds together.  Refrigerate leftover egg mixture.  Chill paste 1 hour (minimum)

Preheat oven to 400 F.  On floured surface, roll pastry dough to a 16 by 14 inch oval.  Losten pastry and carefully fold into quarters.  Place into a 10 by 8 by 2.5 inch oval deep dish baking dish.  Unfold and press into pan.  Trim pastry 1 inch beyond rim of dish.  Brush pastry with some of the leftover egg mixture. Spoon in the filling with juices, mounding in the center.  Bring pastry up over the mound of filling, forming gathers or pleats, leaving the center open.  Brush pastry with egg mixture.

Place pie on a rimmed baking sheet to catch any drips. Ba ke pie 25 minutes (at 400 F). Then lower oven to 350 F.  Cover top of pie with a piece of aluminum foil.  Continue baking for 25 to 35 minutes or until juices bubble in the center.  Cool on wire rack.

Filling:
Trim and cut rhubarb into 1 inch lengths.  Peel, core and cut each apple into 12 wedges.  In a 2 quart saucepan, combine sugar, cornstarch and cinnamon until well blended.  Stir in apples, butter and lemon juice.  Let stand 5 minutes or until sugar begins to disolve.  Cover and cook over medium-low heat until apples soften slightly and sauce thickens and bubbles.  Stir occasionally.  Remove from heat.  Stir in rhubarb.  If rhubarb is not very red add some red food coloring (optional). Let cool at room temperature and then add to pastry (above).