Question: how do you know how much xanthan gum to use?
Answer: Cake, muffin, and quick bread recipes: Add 1/2 teaspoon xanthan gum or guar gum per 1 cup of gluten-free flour used. Cookie and bar recipes: Add 1/2 teaspoon (or less) xanthan gum or guar gum per 1 cup gluten-free flour used.