1. Line a 13 by 9-inch baking dish with two 24-inch-long sheets of 18-inch-wide heavy-duty foil, positioning sheets perpendicular to each other and allowing excess foil to extend beyond edges of pan.
2. Adjust oven rack to lower-middle position; heat oven to 300 degrees.
3. Pat brisket dry with paper towels. Place brisket fat side up on cutting board; using dinner fork, poke holes in meat through fat layer about 1 inch apart. Season both sides of brisket liberally with salt and pepper.
4. Heat 1 teaspoon oil in 12-inch skillet over medium-high heat until oil just begins to smoke. Place brisket fat side up in skillet (brisket may climb up sides of skillet); weight brisket with heavy Dutch oven or cast-iron skillet and cook until well browned, about 7 minutes.
5. Remove Dutch oven; using tongs, flip brisket and cook on second side without weight of Dutch oven until well browned, about 7 minutes longer. Transfer brisket to prepared baking dish.
6. In a small bowl, mix the dry onion soup mix and the wine. Pour over the brisket.
7. Fold foil extensions over and seal. Place in oven and cook until fork can be inserted into and removed from center of brisket with no resistance, 3 1/2 to 4 hours (when testing for doneness, open foil with caution as contents will be steaming) (Oma would cook the brisket at 325 at an hour per pound).
8. Carefully open foil and let brisket cool at room temperature for 20 to 30 minutes.
9. Re-seal the foil and refrigerate overnight.
10. About 45 minutes before serving, adjust oven rack to lower-middle position and heat oven to 350 degrees.
11. While oven heats, transfer cold brisket to cutting board. Scrape off and discard any congealed fat. Use a chef's or carving knife to slice brisket against the grain into 1/4-inch-thick slices, place slices in 13 by 9-inch baking dish. Pour sauce over brisket slices, cover baking dish with foil, and bake until heated through, 25 to 30 minutes. Serve immediately.
To Make and Serve the Brisket on the Same Day