How to make it:
Melt butter in a saucepan over medium heat; then add the flour to create a paste. Whisk together and cook for about 5 minutes to cook out the flour taste. It will be very crumbly at this stage.

In a cup, combine cold milk and the cornstarch together to make a slurry and mix until the cornstarch is dissolved. I like to use So Delicious Unsweetened Coconut Milk because it’s the least flavor impacted milk I have found. It’s the skim milk of coconut milks.

Slowly introduce all liquids - about 1/3 cup at a time - into the paste while whisking together over the heat. Keep adding more while whisking until smooth and fully combined. If it's still too thick, add more chicken stock a little at a time until your desired consistency.

Add the garlic and onion powders, and salt and pepper. Cook for another 5 minutes.

Taste it to see if it needs more salt/flavoring.

Remove from the heat and directly use in another recipe, or refrigerate and store in an airtight container for one week.

Note: About 1 1/3 cups will replace one 10.5oz can of cream of chicken soup.