Heat a skillet over medium-high heat; cook steak, working in batches, until seared and browned on all sides, about 5 minutes. Transfer seared steak to a plate.
Melt butter in the same skillet over medium heat and saute onion until softened, 5 to 10 minutes. Add steak to onion and pour beef stock over steak; season with bay leaves, thyme, salt, and pepper. Bring to a boil, reduce heat to low, cover skillet with a lid, and simmer until steak is tender, 50 minutes to 1 hour 50 minutes. Stir peas and cornstarch into steak mixture; cook uncovered until liquid thickens, about 10 minutes.
Bring a large pot of lightly salted water to a boil. Cook egg noodles in the boiling water, stirring occasionally until cooked through but firm to the bite, about 5 minutes; drain. Serve beef mixture over noodles.
