Vegetables included in a traditional Irish stew are potatoes, leeks, carrots, onions and cabbage, the last of which is optional. Other ingredients include mutton or lamb cutlets, beef stock and flour.
To make traditional Irish stew, brown 1 pound of mutton or lamb cutlets cut into chunks in 2 tablespoons of vegetable oil, and place half of it in the bottom of a casserole dish. Layer half of 2 pounds of quartered and peeled potatoes, 1 cup of roughly chopped onion, 1 cup of diced leek and 1 cup of roughly chopped carrots over the lamb. Top the mixture with the rest of the meat and the other half of the vegetables.
Whisk 2 tablespoons of plain flour into the remaining fat and oil in the browning pan at low heat for a few minutes before stirring in 1 1/2 pints of dark beef stock. Continue to cook the mixture until the flour and fat is completely incorporated and the sauce has thickened, and then pour it over the meat and vegetables in the casserole dish. Sprinkle the top with 3 leaves of thinly sliced cabbage, and cook the stew covered for one hour at 350 degrees Fahrenheit. Regularly check the stew to make sure that the liquid covers everything, and add boiling water as necessary. Season it with salt and pepper to taste before serving.