In a large Dutch oven, heat the vegetable oil over medium-high heat. Add the chopped bacon and cook until crispy. Remove and set aside, leaving the drippings in the pot.
Season the beef cubes with salt and pepper. In the same pot, brown the beef in the bacon drippings in batches, making sure not to overcrowd the pot. Remove the browned beef and set aside.
In the same pot, add the sliced onions and cook until softened, about 5-7 minutes. Add the minced garlic and cook for another minute until fragrant.
Sprinkle the flour over the onions and garlic, stirring to combine. Cook for 2 minutes.
Gradually pour in the Belgian ale, stirring constantly to prevent lumps.
Add the browned beef back to the pot along with the crispy bacon. Stir in the brown sugar, apple cider vinegar, dried thyme, and bay leaf.
Bring the mixture to a simmer, then cover and reduce the heat to low. Let it cook for about 1.5 to 2 hours, stirring occasionally, until the beef is tender.
Once the stew is cooked, taste and adjust seasoning if necessary. Remove the bay leaf before serving.
Serve hot, garnished with chopped parsley.