1. Cut up rhubarb and scald in hot water about 5 minutes. Drain well and place in the bottom of the pie shell.
2. In a small bowl, mix the margarine, flour and sugar together. Beat 2 egg yolks with 3 T water and mix in with the sugar mixture. Pour over the rhubarb.
3. If desired (I don't) make a meringue out of the egg whites and add to the pie. I prefer to cook and eat it without the meringue.
4.Bake in 350 degree oven for 3045 minutes. Serve with vanilla ice cream.