How long do I cook my brisket?
Wrap it in foil, loosely, and roast in your oven at 250°F (121°C) until an internal temperature of 185°F (85°C), this should be about 1 1/2 hours per pound (but CHECK the internal temp with an instant read thermometer). 

Note: an internal temp of 160°F (71°C) is "done" but for a tender slow cook brisket you want to let it go to 185°F (85°C)