Prepare the dry rub by adding the salt, garlic powder, onion powder, chili powder and coarse ground pepper to a small bowl, stir to combine.
Trim the brisket to remove any excess fat. If the brisket has a fat cap on it, remove some to where there’s no more than 1/4 inch of fat remaining.
Pat the brisket dry
Rub the brisket with the dry rub all over. Place the brisket in the slow cooker.
Prepare the BBQ sauce by adding the ketchup, light brown sugar, dijon mustard, worcestershire sauce, garlic powder, onion powder, chili powder, black pepper and sea salt in a bowl. Stir to combine.
Pour 1/2 cup of the sauce over the top of the brisket in the slow cooker and reserve the rest. Cover and store it in the refrigerator.
Cook the brisket on low for 8-10 hours until meat reaches 203 degrees F and is easily pierced with a fork.
Preheat the broiler in the oven on High.
Carefully remove the brisket from the slow cooker and place on a small baking sheet.
Brush 1/2 cup BBQ sauce over the top of the brisket and broil on high heat in the oven for 5 minutes.
Remove from the oven and let the meat rest for 10-15 minutes before slicing.
Slice the meat against the grain, paying attention as brisket can change direction depending on the type of cut you are using.
Serve with the remaining BBQ sauce.