Combine 1 cup flour, 1/3 cup confectioner's sugar and 1/2 cup butter. Press unto bottom of 12" x 9" pan. Bake at 350o F. for 15 minutes. Cool.
If you are using frozen berries: Use two 10-oz. packages. Thaw and drain, reserving liquid. Spread berries over crust. Sprinkle with 3/4 cup chopped walnuts.
If you are using fresh: Use 1-1/2 boxes of fresh raspberries, over the crust, sprinkle with 3/4 cup chopped walnuts. Reserve 1/2 box for juice, if desired.*
Beat 2 eggs with 1/2 cup sugar until light and fluffy. Add 1/2 tsp. salt, 1/4 cup flour, 1/2 tsp. baking powder, and vanilla extract. Blend well. Pour over fruit and walnuts. Bake at 350o F. 30 to 35 minutes until top is dry and toothpick comes out of top layer clean. But DO NOT overbake. Serve with whipped or ice cream and sauce.
For sauce, use Raspberry Claret, or make this sauce: 1/2 cup water, 1/2 cup sugar, 2 tbsp. cornstarch, 1 tbsp. lemon juice and reserved juice. Bring to a boil. Allow to cool before serving.
If you use fresh juice the amount of cornstarch and water may need to be adjusted slightly. When cool, the sauce should pour like room-temperature maple syrup.
*To extract juice, add reserved berries to 1/3 cup water. Mash and boil for a few minutes. Then strain, pressing berries down to force all the juice through.