Slow-Cooker Portobello Dijon Pork Roast Step-by-step instructions

Before you start

Before starting, make sure the slow cooker is clean and dry. Measure out the sliced mushrooms, minced garlic, sour cream, mustard, and au jus so everything is ready to layer. No need to sear the pork or pre-cook the mushrooms – this recipe is designed to be as effortless as possible.

Instructions

Layering the Ingredients

1. 1Layer the Roast and Mushrooms
   Place the pork sirloin roast in the center of a 6-quart slow cooker. Scatter the sliced portobello mushroom caps over and around the roast. Sprinkle the minced garlic evenly over the mushrooms and pork.
   Look for The roast sits in the middle with mushrooms piled on top and garlic scattered over both.
   Tip No need to sear the pork first – the slow cooker does all the work, and skipping the sear keeps this recipe truly dump-and-go.
2. 2Add the Creamy Toppings
   Dollop the sour cream over the top of the roast and mushrooms. Spoon the whole-grain Dijon mustard over the surface. Pour the beef au jus down the side of the slow cooker, avoiding the top of the roast so the seasoning isn't washed off.
   Look for The sour cream and mustard sit in dollops on top, with the au jus pooling around the edges.
   Tip Use whole-grain mustard for its texture and pop of mustard seeds; smooth Dijon works too but won't provide the same visual appeal.

At the end of this phase, the slow cooker contains the pork roast centered in the pot, topped with sliced portobellos and minced garlic.

The sour cream and mustard are dolloped on top, and the au jus is poured around the sides. The setup looks rustic and promising, with the creamy toppings contrasting against the deep brown mushrooms.

Slow Cooking and Shredding

3. 3Cover and Cook Low and Slow
   Cover the slow cooker and cook on low for 8 to 10 hours, until the pork is fork-tender and shreds easily. The internal temperature of the pork should read at least 145°F (63°C) when checked with an instant-read thermometer, but for shredding, it will likely be higher. Let it rest for 3 minutes before slicing.
   Look for The pork is tender enough to pull apart with a fork, and the sauce is bubbling gently around the edges.
   Safe temperature 145°F (63°C) internal temperature (steaks, chops and roasts)
   Tip Resist the urge to lift the lid during cooking – every peek lets heat escape and adds cooking time.
4. 4Shred the Pork
   Using two forks, shred the pork directly in the slow cooker. Stir the shredded pork into the cooking liquid and mushroom mixture so everything is coated in the creamy Dijon pan sauce.
   Look for The pork pulls into long, tender strands and mixes with the mushrooms and gravy.
   Tip If the sauce seems thin, leave the slow cooker on warm with the lid off for 10 minutes to let it reduce slightly.

After 8-10 hours on low, the pork is fork-tender and easily shreds into long strands. The mushrooms have softened and absorbed the sauce, and the liquid has thickened into a silky gravy.

The aroma is rich with garlic, mustard, and savory pork, and the sauce is gently bubbling around the edges.

Resting and Serving

5. 5Let the Meat Rest
   Turn off the slow cooker and let the shredded pork rest in the warm gravy for at least 3 minutes before serving. This allows the juices to redistribute into the meat, keeping it moist and flavorful.
   Look for The pork rests in the sauce, absorbing the creamy, tangy flavors.
   Tip Resting isn't just for roasts – even shredded meat benefits from a few minutes to settle.
6. 6Serve Over Rice or Mashed Potatoes
   Spoon the shredded pork and mushrooms over steamed white rice, mashed potatoes, or crusty bread. Ladle extra pan sauce over each serving.
   Look for Each serving is piled high with tender pork, meaty mushrooms, and plenty of creamy gravy.
   Tip For a lower-carb option, serve over cauliflower rice or alongside roasted vegetables.

The shredded pork rests in the warm sauce for at least 3 minutes, allowing the juices to distribute. The final dish is a generous pile of tender pork and mushrooms, coated in a velvety, tangy gravy. Serve it over rice or mashed potatoes, with extra sauce spooned on top.

Common mistakes

One common mistake is lifting the lid to check on the roast – this releases heat and extends cooking time.

Another is using a lean cut that's too small; if the roast is much smaller than 3 1/2 pounds, check for doneness earlier. Finally, don't skip the resting time after shredding – it lets the juices reabsorb into the meat.

How to tell it’s done

The pork is done when it shreds easily with a fork and the internal temperature reads at least 145°F (63°C), though it will likely be higher after 8-10 hours on low.

The mushrooms should be tender and the sauce should be thick enough to coat the back of a spoon. If the sauce is too thin, simmer with the lid off for 10 minutes.

• Steaks, chops and roasts: 145°F (63°C) in the thickest part, then a 3-minute rest