[header] How to tell if corned beef is cooked [title] Pre-heat your oven to 325 to 350 degrees fahrenheit (163 to 177 degrees celsius). [step] According to the us department of agriculture food safety and inspection service, you should not cook at less than 325 ° f (163 ° c). [title] Place the beef brisket inside a bag, if desired. 
[step] You can cook the corned beef similar to how you cook a turkey, in order to seal in the juices. [substeps] If you are using a bag, you should add 1 tbsp.