Coarsely chop bacon and saute in large skillet until crisp. Remove bacon and reserve. Add onions and cook in bacon fat 20 minutes, raise heat and sprinkle with sugar, toss and stir until well browned. Transfer to strainer.
Stir flour, thyme, salt and pepper together, roll meat into mixture to coat. Brown cubes of meat in vegetable oil, remove meat.
Preheat oven to 325°F. Pour beer into kettle or skillet to stir up all brown bits on the bottom. Return beef, onion, and bacon to pot and bring to a simmer.
Cover and set in middle rack of oven for 1 1/2 hours, stirring occasionally.