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Everybody has their own way for smoking a brisket. To answer your questions. I put my brisket on a cooling rack sitting on an aluminum pan. I put the fat on a rack above the brisket so it drips on the brisket while it smokes. I would not soak your chips. Start with about 1/2 to 1 cup of chips & when the smoke stops add more. Probably every half hour or so. Here is an Au Jus recipe for the pan juices from Chef Jimmy J. Good luck!
ChefJimmy’s Au Jus
1- Lg Onion,
3-4 Ribs Celery
3-4 Peeled Cloves of Garlic
Toss them in a pan under the Beef, and let the whole deal Smoke for one hour,
THEN add 4-6 Cups Beef Broth,
2 Tbs Tomato Paste,
1/2tsp Dry Thyme (4-5 sprigs Fresh)
1-2 ea Bayleaf
Finish the Smoking process to the IT you want.
While the Roast is resting, dump the pan juices veggies and all into a 2-3Qt Sauce pot and add 1Cup Red Wine, something you like to drink, and bring the Jus to a boil, lower the heat and simmer 20-30 minutes. Strain out the veggies and let the Jus rest a minute or so for the Fat to rise. Skim off the bulk of the fat then using strips of paper towel laid on top of the Jus then quickly removed, take off the last little bit of fat.
The purpose of Smoking the Vegetable for 1 hour before adding the Broth and Herbs is...The Smoked vegetables Roast in the Dry heat concentrating their Flavors and Sweetness giving the finished Jus a Richer, Deeper, Full Flavor.
Serve the sliced Beef Au Jus or thicken the Jus to make Gravy