Cut beef into cubes if it isn't already cubed and set aside. Prep potatoes, onion, garlic, celery and carrots and set aside.
Press the sauté button on the Instant Pot and add ghee. Once the pot is hot and shimmering, add the beef cubes. Season beef with Italian seasoning, salt and pepper and toss to coat. Cook beef for 2-3 minutes on each side to brown.
Press the cancel button on the Instant Pot. Add the beef broth, coconut aminos, tomato paste, potatoes, onion, garlic, celery and carrots to the pot.
Secure the lid and valve and press the "soup" button and set to cook for 30 minutes.
While the soup is cooking prepare mushrooms as noted and have the peas ready.
Once the Instant Pot cooking time is up, manually release the pressure.
Remove the Instant Pot lid and press the cancel button. Press the sauté button and add in the mushrooms and peas and stir to mix.
Cook on the sauté setting for 5-6 minutes, stirring occasionally. Or cook until the peas and mushrooms are cooked to your liking.
Press the cancel button on the Instant Pot. Taste the soup and season with any additional salt and pepper as desired. Ladle soup into bowls and serve.
Notes
To make this soup in the slow cooker, simply brown the stew meat in a pan on the stove. Add the stew meat, beef broth, tomato sauce, coconut aminos, potatoes, onion, garlic, celery and carrots to the slow cooker and cook on low for 6 hours or high for 3 hours. When the cooking time is up, stir in the peas and mushrooms to warm and soften for 10-15 minutes.