Is it possible to have a keto stew?
There are literally  keto stew recipes when you search keto stew on google.
From 
Delish.com:

When making keto stew:

choose low carb vegetables
replace potatoes with less starchy root vegetables
use onions and garlic judiciously
small amounts of colorful vegetables add visual appeal
add the vegetables at the last 40-60 minutes of cook time


Also, you can add heavy cream to your stew as the thickening element.