Step #1 Advance Preparation: The day before cooking, place the brisket In a large-ish flat bottomed plastic or glass container.
Step #2 Sprinkle top the garlic, salts, pepper & 3 Tbs.
Step #3 of the liquid smoke over both sides of the beef, then hand rub over all.
Step #4 Return to fat side up, then arrange the onion slices over the top.
Step #5 Seal the container with an air tight lid or with plastic wrap & place this in the refrigerator to marinade overnight (24 hrs).
Step #6 In a 10" Dutch oven mix chili sauce, the remaining liquid smoke, brown sugar, beer, & Worcestershire sauce.
Step #7 Heat using 8-10 briquettes bottom & let simmer until all sugar has been dissolved.
Step #8 Place the beef brisket in a 12" Dutch oven & arrange onions back over the top.
Step #9 Pour 1/2 of the prepared sauce over the brisket then cover & bake using 6-8 briquettes bottom & 8-10 briquettes top for 5 hrs.
Step #10 When beef is tender remove this from the oven & allow to rest for 5 mins.
Step #11 Slice brisket across the grain in thin slices & make sandwiches using the remaining barbecue sauce, reheated.
Step #12 Note: For those of you who like to cook over a campfire this recipe works very well when the oven is buried in hot ashes & allowed to slow cook all day.