My daughter would like to make a vegan cookie recipe from Cherry Bombe. It's also gluten free so calls for xanthan gum. When I went to buy some today, I found that the only way any of my local stores sell it is in a largish bag from Bob's Red Mill. Since we don't require gluten free, wondering if there's a good sub that won't require me to buy a $12 bag for 1 tsp. Can I use guar gum in equal proportion? I did find a small jar of that. Thanks!