Heat a Dutch oven to high (I went to 8) and add butter and oil.
When the pan is steaming a bit, add the meat and cooked uncovered for about 5 minutes.
After 5 minutes, stir the meat and turn over to cook the other sides (still on high heat) for another 5 minutes.
Turn down the heat to medium (about 5) and top with salt, pepper, thyme, basil, oregano, marjoram, paprika, garlic, mushrooms, and celery and blend together.
Cover and cook about 10 minutes (on medium heat).
While cooking, make your slurry with the broth and flour. You will add about ½ cups of the broth to a measuring cup and add all the flour and blend with a fork or whisk until smooth.
After the 10 minutes cooking time above, add the slurry and the rest of the broth to the beef mixture in the pot and blend together.
Reduce heat to low (about 2), cover and cook for about an hour or until meat is tender and gravy is nice and thick. Add more beef broth if gravy gets too thick for your liking.