Start by trimming any excess fat from the brisket. You want it lean, but you also want enough fat to keep it moist during cooking.

In a bowl, mix the celery salt, garlic salt, seasoned salt, and meat tenderizer. Rub this seasoning mixture all over the brisket. Allow it to marinate in the refrigerator for at least two hours or, if time permits, overnight.

Put the seasoned brisket in a freezer bag. Add liquid hickory smoke, Worcestershire sauce, water, apple cider vinegar, and smoked paprika. Seal the bag and massage the mixture into the meat. Refrigerate it again for another few hours.

Preheat your smoker or slow cooker. If you're using a smoker, set it to 225°F. Place the marinated brisket directly on the grill and smoke for around 8-10 hours, or until the internal temperature reaches about 190°F. If using a slow cooker, let it cook on low for 6-8 hours.

Once your brisket is ready, remove it from heat and let it rest for at least 30 minutes. Slice it thinly against the grain. Toast your low-calorie roll, layer it with brisket, aged Gouda, and crispy onion tanglers. Drizzle BBQ sauce over the top or add mayonnaise if you prefer a creamier sandwich.

Serve immediately and enjoy the burst of flavors and textures!