Brown the beef. Turn on sauté function and heat the olive oil, add the beef and brown on all sides. Remove to plate and set aside. Work in batches if needed.
Remove all but a tablespoon of oil and add the curry paste and brown sugar. Whisk together and cook for a minute or two to caramelize. Slowly whisk in the coconut milk, continue whisking to combine and it comes to a boil, about a minute. Turn off sauté mode.
Return browned beef and accumulated juices to pot, add water, tamarind concentrate and fish sauce. Stir to combine. Secure lid and seal, manually set to 'Pressure Cook' on high for 15 minutes.
Quick release the pressure, open the pot and add the potatoes, onions and peanuts. Close the lid and pressure cook on high another 5 minutes.
Quick release the pressure, open and gently stir the beef curry. Taste for seasoning, add more fish sauce or salt, if needed. Transfer to a serving dish and garnish with fresh chopped cilantro, if desired, and serve with jasmine rice.