Slow-Cooker Classic Beef Stroganoff | America's Test Kitchen

Ingredients

• 2 tablespoons vegetable oil
• 1½ pounds white mushrooms , trimmed and halved if small or quartered if large
• 3 onions , chopped fine
• Salt and pepper
• 1/3 cup all-purpose flour
• 1/4 cup tomato paste
• 6 garlic cloves , minced
• 1/2 ounce dried porcini mushrooms , rinsed and minced
• 1 tablespoon minced fresh thyme or 1 teaspoon dried
• 1/2 cup dry white wine
• 1½ cups chicken broth
• 1/3 cup soy sauce
• 2 bay leaves
• 4 pounds boneless beef chuck-eye roast , pulled apart at seams, trimmed, and cut into 1 1/2-inch pieces
• 1/3 cup sour cream
• 2 teaspoons Dijon mustard
• 2 tablespoons minced fresh dill