Ready in less than 30 minutes, is the best way to make this classic beef dinner!
Heat Instant Pot to saute mode. Add oil, onion and garlic. Saute, then add beef. Cook until browned.
Drain beef, then return to the Pot. Add vegetables, Worcestershire, salt, and pepper. Mix well and saute.
While the vegetables are cooking, add melted butter, flour, and beef broth to a bowl. Mix well.
Pour mixture over beef and veggies and stir. Transfer to a casserole dish.
Add water and potatoes to the Instant Pot. Cook on high pressure for 8 minutes. Then, quick release the pressure.
Drain water, then place the potatoes back inside. Mash the until smooth, then add butter and milk.
Transfer mashed potatoes to the casserole dish, spreading over top of the beef and vegetable mixture.
Sprinkle with cheese, then broil for 5 minutes. Serve, and enjoy!