Heat a large sauté pan to medium-high heat, then pour in the oil. Add the vegan beef and sauté it for 5 minutes to create crispy edges. Take the pieces out and set them aside in a small, covered dish for now.
Add the vegan butter to the same pan. Once melted, sauté the onions for 3 minutes until they soften. Add in the mushrooms and cook them for 5 minutes or until they are tender.
Add the garlic and let it cook for 1 minute till fragrant. Sprinkle in the flour and stir it around to coat the vegetables, then cook off the flour taste for 1 minute.
Pour in about 1/4 cup of water and use it to deglaze the pan by scraping the bits from the bottom of the pan. Add the remaining water, bouillon, thyme, salt, pepper, and smoked paprika. Bring this to a boil and then lower the heat to medium-low. Let this cook and thicken for 10 minutes, stirring occasionally.
Turn the heat off and stir in the vegan Worcestershire sauce and Dijon mustard. Once combined, stir in the vegan sour cream. Add the vegan beef back in and stir it into the gravy.
Serve your stroganoff over noodles, mashed potatoes, or rice. Garnish it with more smoked paprika, pepper, fresh parsley, and fresh thyme. Enjoy!