Thank you to all for the recipes I received. This is the one I ended up using, and it was actually quite good.
Cookies
6 egg whites
3/4 cup sugar
1 tsp. vanilla
1 1/2 cups rice flour
2/3 cup melted shortening
Beat egg whites, adding sugar and vanilla gradually, until stiff. Add flour and shortening slowly, beating after each addition. Drop by spoonfuls on hot, greased baking sheet and spread thin with back of spoon. Bake in moderately slow oven (325F) until crisp.
Yield: 72 cookies.