Kielbasa is a large link of sausage shaped like an oval that is compatible with a variety of cooking methods, including the oven. For the best results, the baked kielbasa, or Polish sausage as it's also known, needs a short period of poaching on the stove top. This helps the kielbasa cook throughout without becoming overly browned in the oven. The cooked kielbasa works well on its own, in a sandwich or mixed in with potatoes and vegetables.
Fill a stockpot large enough to hold the kielbasa with beef stock or water. Heat the pot of stock or water to just boiling.
Adjust the heat of the burner so the beef stock or water maintains a simmer. Add the kielbasa ring to the water, allowing it to cook gently for 15 to 20 minutes.
Lift the kielbasa out of the stockpot and place it into a roasting pan. Scoop out 1 to 2 cups of the liquid used in the stockpot, pouring it over the kielbasa in the roasting pan. Add chopped onions and celery to help flavor the kielbasa. Sprinkle the sausage with dry seasonings of your choice, such as garlic or red pepper flakes for additional flavor.
Roast the kielbasa in an oven set to 350 Fahrenheit. Cook the sausage for about 20 minutes until it is crisp and the skin just begins to crack.
Transfer the roasted kielbasa to a serving tray. Slice it into 1/2-inch slices. Adjust the slice size as desired based on how you plan to serve the kielbasa.