Pat the steak dry with paper towels and season evenly with salt and pepper.
In a large skillet over medium-high heat, heat the oil. Add the steak in a single layer and sear for 3-5 minutes, stirring occasionally, until browned on all sides. Work in batches if needed. Transfer to a plate and tent to keep warm.
Reduce heat to medium and add butter. Once melted, add the diced onion and cook for 3-5 minutes, until softened. Add garlic and cook for 1 more minute.
Pour in beef broth, Worcestershire sauce, and soy sauce. Stir to combine, scraping up any browned bits from the pan.
In a small bowl, whisk together cold water and cornstarch. Slowly add to the skillet, whisking constantly.
Bring to a boil, then return the steak (and any juices) to the pan.
Reduce heat to low and simmer for 5 minutes, until heated through and the gravy has thickened.
Garnish with parsley and serve warm over egg noodles.