Dinner · Part 3 of 3: Tips & recipe card

French Onion Butter Pork Sirloin Roast (Slow Cooker) Tips, FAQ & printable recipe

Name: French Onion Butter Pork Sirloin Roast (Slow Cooker)
Prep time: 10 min
Cook time: 8 h
Total time: 8 h 10 min
Cuisine: American
Ingredients: 3 1/2 lb boneless pork sirloin roast; 2 large Vidalia onions, thinly sliced; 1 cup beef consommé; 1/2 cup salted butter (1 stick)

By Clara Weller · Oct 28, 2026

Shredded pork sirloin roast with caramelized onions in a buttery jus 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 beef consommé—it's the backbone of the jus.

If you prefer a thicker sauce, after shredding the pork, remove it from the slow cooker and whisk 1 tablespoon of cornstarch with 2 tablespoons of cold water into the jus. Cook on high for 10-15 minutes until thickened, then return the pork to the pot.

Don't skip the resting time after shredding. Letting the pork sit in the warm jus for 10-15 minutes allows it to reabsorb some of the liquid, making it even more tender and flavorful. If you have time, let the whole pot sit on warm for 30 minutes before serving—it only gets better.

Variations

Cheesy French Onion: After shredding, spoon the pork into oven-safe bowls, top with a slice of baguette and a generous amount of shredded Gruyère or Swiss cheese. Broil until the cheese is melted and bubbly, then serve with extra jus.
Mushroom and Thyme: Add 8 oz of sliced cremini mushrooms and 2 sprigs of fresh thyme to the slow cooker along with the onions. The mushrooms add an earthy depth that pairs beautifully with the butter and consommé.
Spicy Kick: For a little heat, add 1-2 sliced jalapeños or a teaspoon of red pepper flakes with the onions. A splash of hot sauce in the jus before serving also works well.
Balsamic Glaze: After shredding, stir in 2 tablespoons of balsamic vinegar and 1 tablespoon of brown sugar. Cook on high for 10 minutes to create a sweet-tangy glaze that clings to the pork.

Storage and make-ahead

Fridge: Store in an airtight container in the refrigerator for up to 4 days. Keep the pork in its juices to maintain moisture.
Freezer: Freeze in a freezer-safe container for up to 3 months. Thaw overnight in the refrigerator before reheating.
Reheat: Reheat gently in a covered skillet over medium-low heat, adding a splash of beef broth if needed, or microwave in 30-second bursts until hot.

Store leftovers in an airtight container in the refrigerator for up to 4 days. The pork will keep its moisture if stored with some of the jus.

To reheat, warm gently in a skillet over medium heat or in the microwave, adding a splash of beef broth or water if the mixture seems dry. The flavors deepen overnight, making it even better the next day.

This recipe is perfect for meal prep. Assemble the raw ingredients in the slow cooker insert the night before, cover, and refrigerate.

In the morning, place the insert in the slow cooker and cook on low as directed. You can also cook the full recipe, shred the pork, and store it in the refrigerator for up to 4 days or freeze for later.

Serving ideas

The classic way to serve this is over a mound of creamy mashed potatoes, letting the buttery jus soak into every bite.

It's also delicious on toasted baguette slices, topped with a slice of provolone and broiled until bubbly for an open-faced French onion sandwich. A simple side of green beans or a crisp salad balances the richness.

For a low-carb option, serve over cauliflower mash or roasted vegetables. The pork also makes an incredible filling for tacos or sliders—just pile it onto soft rolls and add a spoonful of the onions. Leftovers can be turned into a hearty hash with diced potatoes and fried eggs for breakfast.

Frequently asked questions

Can this recipe be made in a Dutch oven instead of a slow cooker?

Yes. Preheat the oven to 300°F (150°C). Follow the same layering steps in a Dutch oven, cover, and braise in the oven for 3-4 hours, until the pork is fork-tender. Check occasionally and add a little beef broth if the liquid evaporates too much.

Why is the pork dry after cooking?

Pork sirloin is lean, so it can dry out if cooked too long on high heat or if the lid is opened frequently. Always cook on low for the full 8 hours, and avoid lifting the lid. If the roast is smaller than 3 1/2 pounds, reduce the cooking time slightly.

Can this be made with chicken instead of pork?

Yes, boneless, skinless chicken thighs would work well. Cook on low for 4-5 hours until the chicken shreds easily. The safe internal temperature for chicken is 165°F (74°C). The cooking time is shorter, so check early.

How can the sauce be thickened?

After shredding the pork, remove it from the slow cooker. Whisk 1 tablespoon of cornstarch with 2 tablespoons of cold water, then stir into the jus. Cook on high for 10-15 minutes, stirring, until the sauce thickens. Return the pork to the pot.

What can be served with this besides mashed potatoes?

The pork is versatile: serve over egg noodles, polenta, or rice; on toasted bread for a sandwich; or alongside roasted vegetables. A crisp green salad with a tangy vinaigrette helps cut through the richness.

Recipe card

French Onion Butter Pork Sirloin Roast (Slow Cooker)

Prep 10 minCook 8 hTotal 8 h 10 minServes 6

Ingredients

3 1/2 lb boneless pork sirloin roast
2 large Vidalia onions, thinly sliced
1 cup beef consommé
1/2 cup salted butter (1 stick)

Instructions

Place the pork sirloin roast in the center of a 6-quart slow cooker. Scatter the sliced Vidalia onions over and around the roast, then pour the beef consommé around the base, avoiding the top of the meat.
Place the stick of salted butter directly on top of the seasoned roast, right in the center. It will melt and baste the meat as it cooks.
Cover the slow cooker and cook on LOW for 8 hours, or on HIGH for 4-5 hours, until the pork is fork-tender and shreds easily. The onions will turn deeply golden and the liquid will become a rich, buttery jus. Let it rest for 3 minutes before slicing.
Transfer the roast to a cutting board and let it rest for at least 3 minutes. Using two forks, shred the pork into bite-sized pieces, discarding any large fat pieces. Return the shredded pork to the slow cooker and stir gently to coat with the jus and onions.
Spoon the shredded pork and onions over a bed of mashed potatoes, or onto crusty bread for a French onion-inspired sandwich. Ladle extra jus over the top.

Contains: milk, celery

Estimated nutrition per serving

Calories: 480
Protein: 38 g
Carbohydrates: 8 g
Fat: 33 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.