Guinness Onion Garlic Butter Pork Sirloin Roast Tips, FAQ & printable recipe

Tips for success

For the most flavorful result, use a good-quality stout like Guinness Draught. The beer's roasted malt character adds a unique depth that complements pork beautifully.

If you prefer a non-alcoholic version, replace the stout with beef broth and add a teaspoon of Worcestershire sauce for umami. You can also add a bay leaf or a sprig of fresh thyme to the pot for extra aroma, though the cowboy butter already provides plenty of herb flavor.

To make cowboy butter from scratch, mix 4 tablespoons softened butter with 1 clove minced garlic, 1 teaspoon chopped parsley, 1/2 teaspoon dried thyme, and a pinch of smoked paprika. Roll into a log, chill, and slice into medallions.

This can be made ahead and stored in the refrigerator for up to a week. If you don't have pearl onions, use a large yellow onion cut into wedges — it will soften and sweeten similarly, though the texture will be different.

Variations

• Beef Version: Swap the pork sirloin roast for a chuck roast or brisket. The cooking time may need to increase to 10 hours on LOW for a fork-tender result. The stout and butter gravy are equally delicious with beef, and the dish becomes a hearty pot roast.
• Spicy Kick: Add a minced chipotle pepper in adobo sauce along with the onions, or stir a teaspoon of smoked paprika into the cowboy butter. The heat will balance the richness of the stout and butter, giving the dish a subtle warmth.
• Herb-Forward: Add a few sprigs of fresh rosemary or thyme to the slow cooker along with the other ingredients. The herbs will infuse the braising liquid, adding an earthy, aromatic note that pairs well with the garlic butter.
• Low-Carb Option: Serve the shredded pork and gravy over cauliflower mash or roasted spaghetti squash instead of noodles. This keeps all the rich flavor while reducing carbohydrates. The pearl onions add sweetness without the need for added sugar.

Storage and make-ahead

Fridge

Store leftovers in an airtight container for up to 4 days. Reheat gently, adding a splash of broth if needed.

Freezer

Freeze in a freezer-safe container for up to 3 months. Thaw overnight in the refrigerator before reheating.

Reheat

Reheat in a saucepan over medium heat, stirring occasionally, until hot. Add a splash of broth or water to loosen the gravy if necessary.

Store any leftover pork and gravy in an airtight container in the refrigerator for up to 4 days. The flavors will continue to meld, and the dish tastes even better the next day. Reheat gently on the stovetop or in the microwave, adding a splash of broth or water if the gravy has thickened too much. The pork can also be frozen for up to 3 months; thaw overnight in the refrigerator before reheating.

This dish is ideal for making ahead. The entire recipe can be prepared the day before and stored in the refrigerator. The slow cooker does all the work, and the pork actually benefits from resting in the gravy overnight, as the flavors deepen.

To reheat, simply warm the pork and gravy in a pot over medium heat, or in the microwave. If making ahead, consider cooking the buttered noodles fresh just before serving to avoid them becoming soggy.

Serving ideas

Serve this Guinness pork roast over a bed of warm buttered egg noodles, which soak up the rich gravy beautifully. Mashed potatoes, polenta, or crusty bread are equally delicious options.

For a lighter side, steamed green beans or a crisp salad with a tangy vinaigrette provide a nice contrast to the hearty pork. The dish is rich and savory, so a simple side with bright acidity helps balance the flavors.

For a complete meal, add a side of roasted vegetables like carrots or Brussels sprouts. The sweetness of roasted carrots complements the malty stout and garlicky butter. If you have leftovers, use them to make pulled pork sandwiches or tacos with a slaw. The pork is versatile and can be repurposed into many dishes. Garnish with fresh parsley or chives for a pop of color and freshness.

Frequently asked questions

Recipe card

Guinness Onion Garlic Butter Pork Sirloin Roast

Prep 15 minCook 8 hTotal 8 h 15 minServes 6

Ingredients

• 3 1/2 lb boneless pork sirloin roast
• 1 1/2 cups peeled pearl onions
• 1 bottle (12 oz) Guinness draught stout
• 4 tbsp garlic-herb compound cowboy butter, cut into medallions

Instructions

1. Place the pork sirloin roast in the center of the slow cooker insert. Scatter the pearl onions around the roast. Pour the Guinness stout evenly over the meat and onions.
2. Place the medallions of garlic-herb compound cowboy butter on top of the roast, spacing them evenly. Cover the slow cooker with the lid.
3. Set the slow cooker to LOW and cook for 8 hours, or until the pork is fork-tender and shreds easily. Avoid opening the lid during cooking to maintain heat. Let it rest for 3 minutes before slicing.
4. Using two forks, shred the pork directly in the slow cooker. Stir the shredded meat into the cooking liquid so it soaks up the gravy. Let the meat rest in the liquid for 5 minutes before serving.
5. Spoon the shredded pork and onions over warm buttered egg noodles. Drizzle with extra gravy from the slow cooker. Serve immediately.
6. If desired, sprinkle with fresh chopped parsley or chives before serving. This dish is best enjoyed warm, with extra gravy on the side.

Contains: gluten, milk

Estimated nutrition per serving

Calories

480

Protein

34 g

Carbohydrates

18 g

Fat

26 g

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