Step #1 Note: The rice flour you usually find is rather gritty (Arrowhead Mills, so it is best to get your rice flour at an Asian market, etc), where you can find powdered rice flour--it has the same feel as cornstarch.
Step #2 In a small bowl, mix flours & potato starch with a fork until mixed together.
Step #3 In a heavy-bottomed saucepan, melt margarine with oil over med-heat/flame.
Step #4 Whisk flour mixture into oil/butter mixture until it forms a paste.
Step #5 Whisk in chicken stock & rice milk.
Step #6 Add spices & Worcestershire.
Step #7 Bring to a boil, stirring every once in awhile, until thick.
Step #8 If too thick, add more rice milk.
Step #9 If too thin, but has a stronger taste) more flour with 1 T of cold water, mix 1 tsp of (the garbanzo flour thickens better, & then stir in theto the sauce.
Step #10 Repeat if necessary.
Enjoy the Thick , Rich Gluten-Free, Dairy-Free Roux/White Sauce recipe