Use salt and pepper to season the beef.
Set the pressure cooker to sauté and adding butter and vegetable oil. Once the butter has melted, cook the meat in small batches, cooking each batch for about five minutes until the meat is browned. Do not put too much meat at once in the pot. You may need to add more oil as the beef cooks. Then, take out the meat and set it on a separate plate.
Add in your onion to the pressure cooker and sauté for three minutes, stirring as it cooks. Cook until it becomes soft, and then add in beef broth.
Add in bay leaves, tomatoes, parsley, and ground beef as well as juices from the beef. Close the lid and lock it. Cook for 10 minutes on high pressure.
Let the pressure release for five minutes naturally and then do a quick pressure release. Open the lid carefully and add in carrots, potatoes, and celery. Clos the lid and cook for two minutes on high pressure.
Turn off the pressure cooker and allow the pressure to release naturally for five minutes. Use the quick pressure release and then take off the lid. Get rid of the bay leaves.
Mix together flour and water until combined. Add in a cup of warm broth to the flour and mix. Take the resulting slurry and add it to your pot.
Sauté your stew until the sauce begins to boil. Stir it regularly until it begins to thicken. Add in your peas and corn and season with salt and pepper.