Combine the flour and pepper in a plastic bag or bowl, add the beef and toss to coat well.
Heat 3 teaspoons of the oil in a large pot. Add the beef a few pieces at a time; do not overcrowd. Cook, turning the pieces until beef is browned on all sides, about 5 minutes per batch; add more oil as needed between batches.
Remove browned beef chunks from the pot and set aside. Leaving the browned bits in the pot.
Add more oil as needed; saute onions celery and carrots for roughly 3 minutes or until the onoins/celery are soft. Season with salt and peper.
Add garlic and mushrooms (if desired), continue cooking another 3-5 minutes.
To the pot with vegetables, add tomato paste and wine. Simmer until the liquid is reduced.
Add the beef, beef broth and bay leaves. Bring to a boil, then reduce to low. Cover and cook, until the beef is tender, about 1 1/2 hours.
Add the potatoes and simmer until they are tender, about 30 minutes more.
Season to taste with salt and pepper. Add peas frozen if desired. To thicken further, make a slurry of the leftover seasoned flour and cool water, whisk until smooth. Add to stew and simmer to thicken.
Serve immediately with crusty sourdough bread!
Video
Notes
If your beef broth is lacking flavor, add beef bouillon to enhance the flavor. Bouillon can also be used at the end in place of salt to add a beefy flavor ALONG with sodium.