Heat the dutch oven over medium heat, then add the corned beef brisket. Brown all sides of the brisket, then remove it from the dutch oven.
Next, place the onions and carrots in the dutch oven.
Sprinkle the brisket with the spice packet that comes with corned beef. Then pour the bottles of ginger beer and/or water into the dutch oven. Make sure that the liquid reaches the top of the meat.