Cook the bacon in a large nonstick skillet over medium-high heat, stirring occasionally, until crisp, about 6 minutes. Add 1 tablespoon olive oil, then add the onion and cook until softened, about 3 minutes. Add the thyme sprigs, 1/2 teaspoon salt and a few grinds of pepper and cook until the onion is lightly browned, about 5 more minutes. Add the beer, reduce the heat to medium and simmer until reduced by three-quarters, about 15 minutes. Increase the heat to high, pour in the beef broth and simmer until thickened, about 2 more minutes; season with salt and pepper. Discard the thyme.
Meanwhile, bring a pot of salted water to a boil. Add the noodles and cook as the label directs, adding the peas in the last 2 minutes of cooking. Drain and return to the saucepan. Stir in 1 tablespoon butter and season with salt and pepper; keep warm.
Season the steaks with salt and pepper on both sides. Heat the remaining 1 tablespoon each olive oil and butter in a large nonstick skillet over medium-high heat. Working in batches, cook the steaks until lightly browned and just cooked through, about 1 minute per side. Serve with the noodles; top with the braised onions and parsley.