The fats and flavors of a brisket taste best when they are brought out with low cooking temperatures. The end goal with a beef brisket is to achieve a tender and flavorful meat. Some recipes will call for a higher cooking temperature such as 350 degrees Fahrenheit. However, if you have eight to 10 hours to spend, cooking your brisket at 225 degrees Fahrenheit is the ideal method.
Cook the brisket for one and a half to two hours per lb. of meat. There will be natural variations between different briskets including thinness, cut and fat content, so you do not want to stick to an overly generalized cook time. The best method of checking for doneness is by inserting a cooking thermometer into the middle of the thickest part of the meat and checking the temperature.
Check the temperature. The temperature of a fully cooked brisket should fall between 145 to 190 degrees Fahrenheit. You can choose between these temperatures based on your preference for meat doneness.
Wrap the brisket in an oven bag with water to seal in moisture. You can cook the brisket faster at a higher cooking temperature if you seal it in an oven bag with 1/2 cup of water. Using this method, you can cook an 8 to 10 lb. brisket in three hours.