If you are cooking this in your slow cooker, transfer the onions, carrots, mushrooms and garlic from the pan to the cooker (if cooking in a stock pot or Dutch oven, leave the onions and add the potatoes and remaining ingredients) and add the potatoes, the remaining broth, 2 cups (480 ml) water, tamari or soy sauce, Worcestershire sauce, herbs, and salt and pepper. Gently push the herbs into the broth and bring to a boil. Reduce the heat to simmer and cook for one hour, or two or more hours in your slow cooker. The longer you cook the stew the softer the potatoes will become.