Slow Cooker Corned Beef

Saved to Favorites Save to Favorites↓ Jump to Recipe

Looking for a delicious Irish feast for St. Patrick’s Day? Try my slow cooker corned beef and cabbage with Guinness mustard sauce! The beef brisket cooks low and slow in a Crock-Pot with hearty root vegetables until everything is tender and flavorful.

Slow Cooker Corned Beef with Guinness Mustard

It must be the luck of the Irish that you found this recipe! Cooking corned beef in a slow cooker is an ideal method that yields tender slices of beef and perfectly cooked vegetables. The consistent moist-heat in the enclosed vessel ensures that this tough cut of meat gets braised gently.

A hearty combination of root vegetables simmer along with the corned beef, making it a complete meal to celebrate St. Patrick’s Day. To enhance the dish, a Guinness mustard is spread on top of the roast then it’s broiled right before serving to create a flavorful crust. Yes, the words flavorful and Irish food can coexist! 🙂

Crock Pot with corned beef and vegetables inside

What exactly is corned beef?

Corning is another way to describe curing meat in a salted brine for a period of time. The beef brisket comes from the lower chest area of the cow which is rich in fat and connective tissue. It’s typically brined for about a week so that the salty flavors intensify and the meat is better preserved.

The beef is sometimes reddish when you buy it from the store due to pink curing salt #1. Sodium nitrite is used to kill harmful bacteria during the curing process. It’s best to braise this tough cut of beef to gelatinize and tenderize the muscles.

The best cut to purchase

The brisket is often portioned into the flat cut and point cut. The flat cut is what’s often prepackaged at the market, it’s leaner and has a more consistent width which makes it easier to slice. The point cut is thicker with a tapering end with more marbling and tends to cook up more tender and juicy. A nice selection if curing the brisket at home.

Knife slicing pieces of corned beef on a cutting board

Trim the fat to prevent a greasy liquid

There’s typically a large fat cap left on the brisket during the curing process. Trim most of it off, leaving about 1/8-inch layer on top or remove completely. Too much fat when braising will make the liquid greasy.

Use the pre-packaged seasoning packet

For convenience, I use the seasoning packet that comes with the brisket as it adds strong aromatics to the cooking liquid and infuses more flavor in the meat. It’s typically made up of black peppercorns, mustard seeds, coriander, dill, celery seeds, bay leaves, and sometimes red pepper flakes.

How to cook corned beef in a slow cooker

Place the corned beef first in the slow cooker, this ensures it will be submerged in the liquid. Add the potatoes, colorful carrots, celery, onion, and bay leaves along the sides and on top of the beef.

Make sure to cut the vegetables into larger pieces to account for the long cooking time, as they tend to shrink. Sprinkle the spice packet over the ingredients and then pour in the beef broth. Cover and cook until the meat and vegetables are fork-tender.

For a 2-to-3 pound corned beef brisket, cook for about 4-to-5 hours on high, or 8-to-9 hours on low. And that’s before adding in the cabbage. The meat will still appear pinkish in color when fully cooked.

Mustard sauce in a white bowl

Cook the cabbage towards the end

Soggy, mushy cabbage happens when simmering too long in the broth. To avoid this cut the cabbage into 2-inch wedges and place it on top of the beef towards the last hour of cooking. This yields sweet, steamed leaves that still hold its shape and texture.

Checking for doneness

To test for doneness, pierce the thickest part of the beef with a fork, it should slide in and release with ease. Slice a piece of meat off and take a bite, overly chewy pieces are signs of the meat being undercooked, whereas stringy meat is overcooked. Make sure to slice against the grain.

This flavorful sauce is a must!

For a tangy and sweet sauce with a hint of bitterness, combine coarse-ground mustard, honey, and Guinness beer or any stout. After the beef is done cooking, slather on the mustard sauce and serve. However, I also highly recommend broiling the meat in the oven for a few minutes to create a nice crust that clings to the surface. Save the extra sauce to serve on the side for dipping.

Close up photo showing corned beef with mustard sauce crust

Irish recipes you might also like

Can you overcook corned beef in a slow cooker?

Yes! As you get closer to the end of your cooking time, check visually to see if it looks dried out and taste for tenderness. A safe internal temperature for eating is 145ºF (63ºC), although manufacturers typically recommend 160ºF (71ºC) for better texture. Avoid slicing open too many times as you want to retain the juices inside the meat.

Pin this recipe to save for later

Pin This

Slow Cooker Corned Beef with Guinness Mustard

Slow cooker corned beef with Guinness mustard recipe is a traditional Irish feast all in one pot! Tender beef brisket cooked with hearty fresh vegetables.
4.90 from 28 votes
Prep Time15 mins
Cook Time5 hrs
Total Time5 hrs 15 mins
Servings 4 servings
Course Entree
Cuisine Irish


Corned Beef

  • 1 cup celery, stalks, cut into 3-inch pieces
  • 2 cups carrots, cut into 2-inch pieces
  • 1 small yellow onion, cut into 1-inch wedges, root-end left intact
  • 1 pound red potatoes, cut in half
  • 3 cloves garlic, roughly chopped
  • 2 bay leaves, dried
  • 2 pounds corned beef brisket, plus pickling spice packet
  • 1 small cabbage, cut into 2-inch wedges, (about 8 pieces)
  • 4 cups beef broth

Mustard Sauce

  • ¾ cup dijon mustard, coarse ground
  • 2 tablespoons guinness beer, or other stout or porter
  • ¼ cup honey


  • Trim most of the visible fat off of the corned beef, leaving about 1/8-inch layer on top, or remove completely.
  • Place the beef in a 6 quart slow cooker slow cooker, fat side up. Sprinkle with pickling spice.
  • Add the celery, carrots, onion, potatoes, garlic and bay leaves along the sides and remaining on top.
  • Add beef broth to the pot. Cover and cook until corned beef and vegetables are tender, 4 to 5 hours on high or 8 to 9 hours on low setting.
  • Arrange cabbage on top of the corned beef, cover and continue to cook until cabbage is tender, 30 to 60 minutes on high.
  • The meat is done when a fork can easily pierced into the meat, and the internal temperature reaches at least 160ºF (71ºC).
  • In the meanwhile mix mustard sauce, cover and refrigerate.
  • Remove the beef from the pot, trim off any excess fat is desired. Transfer to a foil-lined baking sheet.
  • Spread a thin layer of the mustard sauce on top of the surface.
  • Broil the beef about 6-inches away from the top heating element, until the mustard is lightly browned, about 5 to 8 minutes.
  • Slice corned beef against the grain and serve with vegetables and extra mustard sauce.


Apple juice can be substituted for the Guinness beer.
Nutrition Facts
Slow Cooker Corned Beef with Guinness Mustard
Amount Per Serving
Calories 516 Calories from Fat 270
% Daily Value*
Fat 30g46%
Saturated Fat 12g60%
Polyunsaturated Fat 0.4g
Monounsaturated Fat 1g
Cholesterol 140mg47%
Sodium 3225mg134%
Potassium 686mg20%
Carbohydrates 24g8%
Fiber 5g20%
Sugar 8g9%
Protein 36g72%
Vitamin A 10250IU205%
Vitamin C 25.6mg31%
Calcium 40mg4%
Iron 2.3mg13%
* Percent Daily Values are based on a 2000 calorie diet.

Tried this recipe?

Tag me on Instagram. I'd love to see how it turns out!

Tag @jessica_gavin

Filed under:

This post may contain affiliate links. Please read my disclosure policy.

Jessica Gavin

I'm a culinary school graduate, cookbook author, and a mom who loves croissants! My passion is creating recipes and sharing the science behind cooking to help you gain confidence in the kitchen.

Jessica's Secrets: Cooking Made Easy!
Get my essential cooking techniques that I learned in culinary school.
Jessica Gavin standing in the kitchen

You May Also Like

Reader Interactions

16 Comments Leave a comment or review

    • Jessica Gavin says

      Thank you so much Jamie! I’m so happy that you enjoyed the recipe and that it will be a tradition 🙂

  1. Danielle D. says

    Your recipe sounds amazing! I have an odd question. Does leaving the cabbage in the crock pot for 45 min on high/1.5 hrs on low cause your kitchen to stink? I don’t know how long it can be cooked before it starts to give off that awful smell. Thank you!

    • Jessica Gavin says

      Thank you Danielle! When cabbage is cooked too long it starts to emit a rotten egg smell from hydrogen sulfide, a gas that is released when the cabbage has been overcooked. It’s a challenge since you are slow cooking, so if you want to avoid the smell or at least reduce it, I would cook the cabbage separately in boiling water until tender, right before you serve. great question! For this recipe, I didn’t feel the smell from the cabbage was too strong because of the cured meat and seasonings cooking with the cabbage.

  2. Nancy says

    Hi, looks so good! Will be making this for sure this year. Question, on the nutrition facts, is that based on the recipe serving two people, and the label is for one serving? Thanks!

  3. susan troccoli says

    I have to ask: In the 2nd picture (with the crockpot) there are 2 red and yellow speckled logs with a solid yellow center, almost like a pretzel w/cheese in the middle. Can’t find anything in the recipe that this could be. What is it?

    • Jessica Gavin says

      Great questions Susan! Those are just purple carrots (heirloom carrots), however, you can use whatever carrots are available.

  4. Michelle says

    This corned beef was fantastic! I used a point tip, 3#, rubbed the seasoning, kosher salt and some pepper. Then added 4 cups beef broth with a tablespoon mango rice vinegar for the acid component. 5 hours on low, internal temp 185. Just perfect! I was unsure if I wanted to do the oven or slow cooker method and am so glad I used the slow cooker! Thank you for the great recipe!

  5. analisa says

    I had never made corned beef and cabbage before, but I found this recipe and decided to give it a go. It was outstanding. I followed the recipe exactly as Jessica explains on this webpage. The meat was very tender and so flavorful, and the mustard was fantastic. My boyfriend and I both had two helpings last night for dinner…. and we have a little left for lunch today. This will be the only corned beef recipe for me going forward.

Leave A Reply

Recipe Rating