Slow-Cooker Beer-Braised Brisket

Finely chop garlic in a food processor. Add brown sugar, mustard, oil, black pepper, cumin, paprika, cayenne, and 2 tablespoons salt and process until smooth. Rub all over brisket, working into crevices. Wrap in plastic; chill 1–2 days. Let meat sit out until it’s room temperature, about 1 hour.

Scatter onions in a 4–6-quart slow cooker and add brisket, fat side up. Add beer and 1 cup water. Cover and cook until meat is very tender, 7–8 hours on low or 4–5 hours on high.

Heat broiler. Transfer brisket, onions, and any braising liquid to a large oven-proof skillet or roasting pan. Broil brisket, uncovered, until top is browned and crisp, 5–10 minutes.

Let brisket cool slightly. Remove from pan and shred or slice. Remove onions with a slotted spoon; mix into brisket. Taste and moisten with some cooking liquid and season with salt, if needed.

Do ahead: Brisket can be braised 1 day ahead. Let cool; cover and chill. Reheat, covered, at 325° for 1½ hours.