I tried my regular chocolate chip cookie recipe, and then substituted the gluten-free flour blend. It took 2 tries to get it right, and they are not as "fat" as the regular ones, but they have a good flavour, and after I increased the flour blend they only spread a little, and not all over the pan. A pretty good cookie that got the thumbs up from the Junior High Boys.
1/2 cup hard margarine, softened
1/2 cup white sugar
1/2 cup brown sugar
1 large egg
1/2 teaspoon vanilla
1 cup rice flour*
1/2 cup tapioca starch*/flour
1/2 cup cornstarch
1 teaspoon guar gum*
1 teaspoon baking powder
1/2 teaspoon baking soda
1/2 teaspoon salt
1 cup chocolate chips
Cream together margarine and the sugars. Add egg and vanilla. Mix in rice flour, tapioca starch, cornstarch, guar gum, baking powder, baking soda and salt. Add chocolate chips.
Divide dough into 24 balls, and place about 2 inches apart on lightly greased cookie sheets. NOTE: use margarine to grease pans; or make sure your cooking oil spray has no flour added to it.
Bake at 325*F for about 10 minutes. Let stand/cool on cookie sheets for a few minutes, then transfer to cooling racks.
*rice flour is readily available at most grocery stores. Tapioca starch and guar gum were available at Nutter's Bulk Foods for a very reasonable price. A large bag of tapioca starch was about $3, and the guar gum was about $6 for 250 g.