In a large pot or dutch oven, heat oil. When hot, add meat and 1 tablespoon flour. Toss and brown meat on all sides.
Remove meat from pot and discard all but 2 tablespoons fat. Add garlic and onions and cook until tender. Stir in remaining flour and cook until onions begin to brown. Stir in beef stock, tomato paste, thyme, rosemary, vinegar, and pepper. Add beef and bring to a boil. Reduce heat to a simmer, cover and cook for 1-1/2 hours.
Heat a small skillet over medium heat and add 2 tablespoons butter. Add mushrooms and small white onions and cook until all liquid has been absorbed.
Add mushrooms and onions to meat mixture. Cover and simmer about 30 minutes more. Adjust seasonings and serve.
Tips
We used the Gluten free Pantry’s Country French Bread Mix as a straight substitution for flour.