This easy Crock Pot Beef Stroganoff recipe is made with sirloin steak, mushrooms, and a creamy white sauce. It's perfect for a weeknight dinner or a comforting weekend meal and is easy to prepare with the help of your slow cooker!
Cut the beef into 1" cube and trim off excess fat—season with salt and black pepper.
Heat olive in a large skillet over medium heat, add seasoned beef, and sear each side for 30 seconds in small batches. Remove beef and place in the slow cooker.
Add 3 cups of beef broth to the skillet to deglaze the pan. Then pour into the slow cooker.
Then, add thyme, mushrooms, Worcestershire sauced, Dijon mustard, cream of mushroom soup, and garlic to the slow cooker. Stir until well combined.
Cover and cook on high for 4-5 hours or on low for 7-8 hours or until the beef is tender.
Thirty minutes before cook time is up. In a medium bowl, whisk together ½ cup of beef broth and cornstarch until there are no lumps. Then whisk in sour cream and pour into the slow cooker.