Dec 23, 2020 · The best Slow-Cooker Beef Stroganoff is the kind that makes prep and cleanup a breeze. Plus, creamy beef stroganoff in the slow cooker is one of those delicious classics that never disappoints, especially with our easy steps. Once you brown the beef strips with onion and garlic in butter, add it to your slow cooker with golden mushroom soup, and fresh mushrooms. Remove the chicken and keep warm. Mix the cornstarch and water in a small bowl. Stir the cornstarch mixture into the slow cooker. Cook on High until the sauce has thickened, about 15 minutes. Return the chicken to the slow cooker and heat through. Top with fresh cilantro and almonds before serving. I made a few small changes as I didn't have all the ingredients from the recipe. In the slow cooker I placed the chicken (frozen), 1 cup of chicken broth, 1 tbsp of Italian spices and 1 tsp of fresh basil. I cooked this on low for 3-4 hours. I then sauted the onions and garlic in butter as directed.