Hi Mara. The one you posted differs, it is primarily rice flour then tapioca and tater starches.
Here below is the one I’ve been using - also if you didn’t see my comments above about working with it you may want to check that, too.
The main ingredient is “Gluten Free Wheat Starch” which they state has been processed to meet FDA requirements for GF food. My sister had some concern about that (despite knowing that my more-sensitive daughter had eaten it with no problem). Still, if it is a concern you might try a half-recipe (single ~ 10-inch pie) and maybe only eat one slice as a test.
Full ingredients listed below in case you are sensitive to any of them.
The nice thing about this one vs the one you posted (besides it’s out of stock) is the Bread/Pizza mix says it only makes 2 pies whereas this one should get me a (scant) 8 pies, with the price differential being $8 vs $13
Full ingredients:
GF wheat starch, corn starch, sorghum flour, cellulose/psyllium fiber blend, inactive yeast (I believe this is only for a more yeasty flavor, you do add yeast when mixing as well), and xanthan gum.
Another KA GF product that I’ve had some middling success with in pizza is their GF Bread Flour. I need to play around with it a bit more to get it just right. But when I found the direct pizza dough product I quit trying, given they are the same price at my local grocery. Still, if you can’t find the pizza product, the bread flour can be used. This one also relies heavily on that GF wheat starch, adds some pea protein and has more of the c/p fiber blend than sorghum flour. They say it’s a direct drop-in for bread recipes, except that you need to bump the hydration by 60-90 grams water per 120 g flour used. Oh, and it seems to rise a lot faster than regular bread flour.
Edit to add:
We tried Bob’s first GF “1-for-1” and it was horrid. Number 1 ingredient was garbanzo flour, which should have tipped me off that it wasn’t suited for anything but biscuits (because the baking powder helps mask the flavor). I’ve had a more recent Bob’s that was okay, but we used it up and I stupidly forgot to write down which one it was before I threw away the bag.
Still, I’m really happy with the KA stuff. We’ve got yet a third bag, their “measure for measure” which is intended for sweets (not yeasted products) and my daughter made a really lovely white cake with it. I couldn’t even tell it was GF. This product is different than their GF “AP” flour but I’m not positive of the details. I don’t know if we’ve ever used the GF AP or not.