Get your 6-quart crockpot or slow cooker out and ready.
Slice and chop up the onions, carrots, and celery.
It's also helpful to have the beef broth ready to use and the flour pre-measured and set to the side.
Heat 2 Tbs. Butter to sizzling over medium-high heat in a large frying pan or large skillet.
Add the celery, carrots and onions. Sauté until onions start to look translucent.
Dump in the slow cooker.
Place the frying pan back on the stovetop over medium-high heat and add the raw beef stew meat.
Brown the outsides of the stew meat. You don't need to make sure it's cooked all the way through because it will finish cooking as it simmers in the crock pot.
Add flour to browned meat and mix to make a paste.
Add 3 cups of the beef broth, a little at a time to the meaty flour mixture while mixing well to make a gravy.
Simmer to thicken slightly.
Dump into the crockpot over the vegetables.
Peel, slice, and dice the potatoes, I prefer smaller pieces and add them to the slow cooker.
Pour in the remaining broth.
Some people like to add a bay leaf to their stew. If you would like to do that, this is when you would add it.
Put a lid on and cook on high heat for 4-5 hours or on low heat for 8 hours.
The gravy in this stew may seem too thin at first, but it will thicken as it cools.
If you would like, you could add a splash of Worcestershire sauce or fresh rosemary to this crock pot beef stew before serving.