Keto replacement for flour I would like to know what to use and how much, in place of flour to thicken the sauce in the following recipe and make it keto.
This is the full recipe:


2 Tbsp butter
1 small yellow onion, diced
4 large garlic cloves, minced
1/2 cup chicken broth
1/2 tsp garlic powder
1/4 tsp pepper
1/2 tsp salt
8 oz sliced mushrooms (optional)
1 1/2 lbs boneless skinless breasts sliced into 1/2 inch filets
1 cup half and half
2 Tbsp flour
1/2 cup parmesan cheese
3 oz coarsely chopped spinach
Salt and freshly ground pepper



Turn your Instant Pot to the saute setting (more). When the display reads HOT add in the butter. Once the butter is melted add in the onions and saute for about 3-4 minutes. Add in the garlic and saute for 30 seconds. Add in the chicken broth, garlic powder, pepper and salt. Stir. Add in the mushrooms (if using) and chicken.
Cover the pot and secure the lid. Make sure valve is set to sealing. Set the manual/pressure cook button to 6 minutes (this is the cooking time for the 1/2 inch pieces of chicken breast, if they are thicker than that you may need more time). Let the pressure release naturally for 10 minutes and then move the valve to “venting.”
Remove the lid.  Use tongs to place the chicken on a platter. Loosely cover with foil. Turn the Instant Pot to the saute setting. Warm the half and half up in a pyrex measuring cup for 45 seconds in the microwave. Whisk the flour into the half and half until it’s smooth. Whisk the mixture into the Instant Pot. This will thicken up the sauce in a few minutes. Add in the parmesan cheese. Add in the spinach. Salt and pepper to taste. If using pasta, drain any water off of the pasta and stir into the pot.
One option is foregoing thickener entirely. I regularly make sauces with those proportions and no thickener and find them perfectly fine, texture wise.
Another option is substituting the half and half with full cream or even switch 1/3-1/2 of it for cream cheese. Or, similarly, add more parmesan or another cheese to thicken the sauce. All of those substitutes will make for a thicker sauce without any further additions.
Otherwise, xantham gum is keto friendly. You want to add about 0.2% xantham gum by weight to slightly thicken a sauce, so about 1.5 grams for your recipe (I recommend weighing your sauce on a kitchen scale and calculating the amount precisely). I would mix it well with a small amount of cream like for a cornstarch slurry, before mixing that into the rest of the liquid. Like Stephie pointed out in the comments, mixing any powder into a hot liquid is very difficult.