To master Tx style brisket requires patience, practice & more patience. Find a good rub first. I used to make my own but while on business in Chico California I used a rub from there called Pappys Choice Seasoning & absolutely loved it. The Cali's use it on their Tri-Tips. It adds wonderful flavor & I brush on Dijon Mustard after giving the brisket a good rub. I prefer a 50/50 mixture of Pecan & Hickory wood or chips. Cook brisket low & slow for about 12-16 hrs about 200 degrees or less. I have tried covering the top of the brisket with sliced onions & then covering with foil, the results were 50/50 on opinions. Some liked it, some didn't. My rub recipe used 1 cup Paprika, 2 Tblsps each of garlic & onion powder, 1 Tblsp. kosher salt, 1 tsps. white pepper, 1/2 tsps cayenne pepper & 1 Tbsp of ground lemon peel. Mix all together rub down brisket really, really well & brush on Dijon Mustard just ot coat meat, not to thick. Sprinkle more rub in top of mustard if desired. Cook low & slow for about 12-16 hrs about 200 degrees or less. Let meat rest for about 30-40 minutes before slicing. This should establish a good smoke ring. Cook brisket fat side up as well. This takes practice to perfect for not all smokers are the same, the moisture content of the wood, blah, blah, blah. It just takes practice to achieve YOUR idea of what is a great brisket. Pappy's Seasoning can be purchased on their website www.pappyschoice.com, if you want to buy some, buy Pappys Choice Seasoning. Let me know how these work for you...enjoy!