Peel the onions and slice them into thin, consistent strips to ensure they caramelize evenly.
Mince the garlic clove into a fine paste and set it aside.
Heat the vegetable oil in a large skillet over medium-high heat until it shimmers.
Add the sliced onions to the skillet and cook, stirring occasionally, until they turn a deep golden brown and soften.
Push the onions to one side and add the ground beef to the skillet. Brown the meat thoroughly, breaking it apart with a spatula to ensure even searing.
Once the beef is browned and the fat has rendered, combine the beef with the caramelized onions.
Add the minced garlic and cook for another minute until fragrant.
Pour in the Worcestershire sauce and scrape the bottom of the pan to incorporate the browned bits (fond) into the meat mixture.
Season with salt and pepper to taste and serve immediately.