Dinner · Part 3 of 3: Tips & recipe card

Guinness Onion Butter Pork Roast: 5-Ingredient Crockpot Dinner Tips, FAQ & printable recipe

Name: Guinness Onion Butter Pork Roast: 5-Ingredient Crockpot Dinner
Prep time: 10 min
Cook time: 8 h
Total time: 8 h 10 min
Cuisine: Irish-American
Ingredients: 3 1/2 lb boneless pork sirloin roast; 2 cups peeled white pearl onions; 1 bottle (12 oz) Guinness draught stout; 1 stick (4 oz) salted butter

By Clara Weller · Oct 28, 2026

Shredded pork sirloin roast with pearl onions in a slow cooker

Prep: 10 min
Cook: 8 h
Total: 8 h 10 min
Serves: 6

Tips for success

For the best flavor, use a good-quality stout like Guinness. The beer's roasted notes are essential to the dish. If you prefer a milder beer flavor, use a porter or a brown ale.

The butter is non-negotiable—it adds richness and helps create the silky sauce. If you want a thicker sauce, you can remove the pork and onions and simmer the liquid on the stovetop for a few minutes to reduce it.

This recipe is incredibly forgiving. The slow cooker does all the work, so you can prep it in the morning and come home to a finished dinner. The pork can be served over mashed potatoes, rice, or polenta, or piled onto rolls for sandwiches. Leftovers keep well and can be reheated gently on the stovetop or in the microwave.

Variations

Beef Version: Substitute a 3-pound beef chuck roast for the pork. Cook on low for 8-10 hours until fork-tender. The stout and butter work equally well with beef, creating a rich, hearty dish.
Add Herbs: Add 2 sprigs of fresh thyme or rosemary to the slow cooker along with the other ingredients. The herbs infuse the pork and sauce with aromatic flavor. Remove before serving.
Spicy Kick: Add 1-2 teaspoons of smoked paprika or a pinch of cayenne pepper to the butter before placing it on the roast. This adds a subtle warmth that complements the stout.
Onion Lovers: Increase the pearl onions to 3 cups, or add a chopped yellow onion for extra sweetness. The onions become soft and caramelized during the long cooking time.

Storage and make-ahead

Fridge: Store in an airtight container in the refrigerator for up to 4 days. Reheat gently on the stovetop or microwave, adding a splash of water if needed.
Freezer: Freeze in a freezer-safe container for up to 3 months. Thaw overnight in the refrigerator before reheating.
Reheat: Reheat gently on the stovetop over low heat or in the microwave in 30-second bursts, stirring occasionally.

Store any leftover pork and sauce in an airtight container in the refrigerator for up to 4 days. The flavors will continue to meld, making leftovers even more delicious.

Reheat gently on the stovetop over low heat, adding a splash of water or broth if the sauce has thickened too much. The pork can also be frozen for up to 3 months.

This recipe is ideal for making ahead. Assemble the slow cooker the night before, cover, and refrigerate. In the morning, place the insert in the slow cooker and cook on low as directed.

If you're short on time, you can also cook the pork a day ahead, shred it, and store it in the refrigerator. Reheat gently with the sauce when ready to serve.

Serving ideas

Serve this pork over creamy mashed potatoes to soak up the buttery stout jus. The richness of the pork pairs beautifully with the smooth potatoes. For a low-carb option, serve it over cauliflower mash or alongside roasted vegetables. The pearl onions are a delicious side in themselves—don't leave them behind.

For a casual meal, pile the shredded pork onto toasted buns with a little of the sauce for a hearty sandwich. Add a side of coleslaw or pickles to cut through the richness.

The dish also works well with crusty bread for dipping into the jus. Garnish with fresh parsley or chives if you like, though it's delicious as-is.

Frequently asked questions

Can this recipe be made without beer?

Yes, substitute the Guinness with an equal amount of beef broth or a non-alcoholic stout. Add a splash of balsamic vinegar or Worcestershire sauce (if not avoiding gluten) to mimic the depth that beer provides.

How long does the pork need to cook?

Cook on low for 8 hours, or on high for 4-5 hours. The pork is done when it reaches an internal temperature of at least 145°F (63°C) and shreds easily with a fork. Cooking on low yields the most tender results.

Can this recipe be doubled?

Yes, but ensure the slow cooker is large enough (at least 6 quarts) and the ingredients fit without overflowing. Increase the cooking time by 1-2 hours if needed, and check that the pork reaches the safe internal temperature.

Why is the sauce not thickening?

The sauce is meant to be a thin jus, not a thick gravy. If a thicker sauce is desired, remove the pork and onions and simmer the liquid on the stovetop for 10-15 minutes to reduce it, or whisk in a cornstarch slurry.

Can the pork be cooked on high instead of low?

Yes, cook on high for 4-5 hours, but the meat may be slightly less tender than when cooked on low. Always check the internal temperature to ensure it reaches at least 145°F (63°C).

Recipe card

Guinness Onion Butter Pork Roast: 5-Ingredient Crockpot Dinner

Prep 10 minCook 8 hTotal 8 h 10 minServes 6

Ingredients

3 1/2 lb boneless pork sirloin roast
2 cups peeled white pearl onions
1 bottle (12 oz) Guinness draught stout
1 stick (4 oz) salted butter

Instructions

Place the pork sirloin roast in the center of a 6-quart slow cooker. Scatter the pearl onions around the roast, tucking some underneath for even cooking.
Slowly pour the Guinness stout over the roast and onions. The liquid should come about halfway up the sides of the roast, not fully submerge it.
Place the whole stick of salted butter on top of the roast. It will melt and baste the meat as it cooks.
Cover the slow cooker and cook on LOW for 8 hours, or until the pork is fork-tender and easily shreds. Avoid opening the lid during cooking to maintain temperature. Let it rest for 3 minutes before slicing.
Remove the roast to a cutting board. Let it rest for at least 3 minutes, then shred with two forks. Return the shredded pork to the slow cooker and stir into the juices.
Serve the shredded pork and onions over mashed potatoes or with crusty bread, spooning the buttery stout jus over the top.

Contains: gluten, milk

Estimated nutrition per serving

Calories: 450
Protein: 35 g
Carbohydrates: 10 g
Fat: 28 g

Automatic estimate from the ingredient list, not laboratory-verified.

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This recipe is based on a short cooking video and is published under the pen name Clara Weller. It was checked before publication, but errors can slip through. Nutrition, when shown, is an estimate. Read more in our editorial policy and on our food safety page.