Slow-Cooker Brisket & Onions over Buttery Mashed Potatoes


This brisket is seasoned with tangy mustard, sweet turbinado sugar and pungent garlic. Substitute brown sugar for the turbinado, if desired, and use the tube variety of tomato paste so any leftovers stay fresh longer. We recommend serving this braised beef over mashed potatoes, but it'd be just as delicious over rice, spaghetti squash or pasta.

Prep Time:
20 mins
Additional Time:
8 hrs
Total Time:
8 hrs 20 mins
10 servings


  • 3 tablespoons whole-grain mustard

  • 2 tablespoons turbinado sugar

  • 3 garlic cloves, minced (about 1 tablespoon)

  • 2 tablespoons olive oil

  • 2 ½ pounds beef brisket, trimmed

  • 1 teaspoon kosher salt

  • 1 teaspoon black pepper

  • 2 medium red onions (6 to 8 ounces each), each cut into 8 wedges

  • 1 cup unsalted beef stock

  • 2 tablespoons tomato paste

  • 1 fresh rosemary sprig

  • 1 (24 ounce) package frozen steam-and-mash potatoes (such as Ore-Ida Steam n' Mash Cut Russet Potatoes)

  • 1 tablespoon unsalted butter, cut into pieces

  • ¼ cup chopped fresh flat-leaf parsley


  1. Stir together the mustard, sugar, and garlic in a small bowl, forming a paste; set aside.

  2. Heat the oil in a large nonstick skillet over medium-high. Sprinkle the beef with the salt and pepper. (If needed, cut the beef into 2 pieces to fit in the skillet and slow cooker.) Add the beef to the hot skillet; cook until browned, about 4 minutes on each side. Transfer the beef to a 5- to 6-quart slow cooker, reserving the drippings in the skillet. Spread the paste over the brisket.

  3. Add the onions to the reserved drippings in the skillet; cook, turning once, until the onions are lightly browned, about 4 minutes. Place the onions on the top of the beef in the slow cooker, reserving the drippings in the skillet. Whisk together the beef stock and tomato paste in a medium bowl; add the stock mixture to the reserved drippings in the skillet, and cook, stirring to loosen the browned bits from the bottom of the skillet, about 30 seconds. Pour the stock mixture over the onions and beef in the slow cooker. Add the rosemary sprig. Cover and cook on LOW until very tender and the beef is beginning to fall apart, about 8 hours. Transfer the beef to a cutting board, reserving the cooking liquid in the slow cooker. Discard the rosemary sprig. Let the beef rest 10 minutes.

  4. Meanwhile, prepare the potatoes according to the package directions. Transfer to a serving bowl, and stir in the 2 tablespoons butter until melted.

  5. Thinly slice or coarsely shred the beef. Serve the beef and onions over the mashed potatoes; sprinkle with the parsley, and serve with the reserved cooking liquid.

Nutrition Facts (per serving)

335 Calories
16g Fat
18g Carbs
26g Protein
Nutrition Facts
Servings Per Recipe 10
Calories 335
% Daily Value *
Total Carbohydrate 18g 7%
Dietary Fiber 2g 7%
Total Sugars 4g
Added Sugars 3g 6%
Protein 26g 52%
Total Fat 16g 21%
Saturated Fat 6g 30%
Sodium 628mg 27%

Nutrition information is calculated by a registered dietitian using an ingredient database but should be considered an estimate.

* Daily Values (DVs) are the recommended amounts of nutrients to consume each day. Percent Daily Value (%DV) found on nutrition labels tells you how much a serving of a particular food or recipe contributes to each of those total recommended amounts. Per the Food and Drug Administration (FDA), the daily value is based on a standard 2,000 calorie diet. Depending on your calorie needs or if you have a health condition, you may need more or less of particular nutrients. (For example, it’s recommended that people following a heart-healthy diet eat less sodium on a daily basis compared to those following a standard diet.)

(-) Information is not currently available for this nutrient. If you are following a special diet for medical reasons, be sure to consult with your primary care provider or a registered dietitian to better understand your personal nutrition needs.

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