Slow-Cooker Black Pepper Steak with Bell Peppers Step-by-step instructions

Before you start

Before starting, slice the sirloin into thin strips, about 1/4-inch thick. Cut the onion into thin slices and mince the garlic. Crack the black peppercorns coarsely — a mortar and pestle or the bottom of a heavy pan works well.

Measure out the oyster sauce, dark soy sauce, and Shaoxing wine. Have the bell peppers washed and sliced into strips, but do not add them until the final 30 minutes.

Instructions

Layer and Slow-Cook

1. 1Layer the Steak and Aromatics
   Place the sliced sirloin steak into the slow cooker insert. Add the sliced onion, minced garlic, and coarsely cracked black pepper. Pour the oyster sauce, dark soy sauce, and Shaoxing wine over the top. Use a wooden spoon or spatula to toss everything together until the steak is evenly coated in the sauce mixture.
   Look for The steak strips are fully coated in a dark, glossy sauce with visible pepper specks.
   Tip For the best flavor, crack the peppercorns just before adding — freshly cracked pepper is much more aromatic.
2. 2Cover and Cook on Low
   Cover the slow cooker with the glass lid. Set the heat to LOW and cook for 4 hours. During this time, the steak will become tender and the sauce will deepen in flavor. Avoid lifting the lid during cooking to keep the heat steady. Let it rest for 3 minutes before slicing.
   Look for After 4 hours, the steak is fork-tender and the sauce is bubbling gently around the edges.
   Safe temperature 145°F (63°C) internal temperature (steaks, chops and roasts)
   Tip If your slow cooker runs hot, check at the 3.5-hour mark — the steak should be easily pierced with a fork.

After the first 4 hours, the kitchen smells deeply savory and peppery. The steak has darkened to a rich brown, and the sauce is bubbling gently with a glossy sheen.

The meat should be easily pierced with a fork, and the onion will have softened into the sauce.

Add Peppers and Finish

3. 3Add the Bell Peppers
   After 4 hours, open the lid and add the sliced tri-color bell peppers. Stir them into the sauce gently. Cover and cook for an additional 30 minutes on LOW. The peppers should remain slightly crisp, adding a fresh crunch to the rich sauce.
   Look for The peppers have brightened in color but still hold their shape when stirred.
   Tip Cut the peppers into similar-sized strips so they cook evenly in the short time.
4. 4Check the Steak Temperature
   Use a meat thermometer to check the internal temperature of the thickest steak strip. It should read at least 145°F (63°C). If it hasn't reached that temperature, continue cooking for another 10 to 15 minutes and check again. Once done, turn off the slow cooker. Let it rest for 3 minutes before slicing.
   Look for The thermometer reads 145°F (63°C) or higher.
   Safe temperature 145°F (63°C) internal temperature (steaks, chops and roasts)
   Tip Because the steak is in thin strips, it will likely be well above 145°F after the long cook — that's fine, the slow cooker tenderizes it.

The bell peppers have brightened to vivid red, green, and yellow, and they've softened just slightly while keeping a pleasant crunch. The sauce has thickened further, coating the peppers and meat in a sticky, aromatic glaze.

Rest and Serve

5. 5Rest the Steak
   Let the steak rest in the slow cooker with the lid off for at least 3 minutes. This allows the juices to redistribute and the sauce to settle. Do not skip this rest — it keeps the meat moist and tender.
   Look for The sauce has stopped bubbling and the meat looks glossy.
   Safe temperature 145°F (63°C) internal temperature (steaks, chops and roasts)
   Tip Resting is especially important for whole cuts of meat, even in a slow cooker.
6. 6Serve Over Rice
   Spoon the black pepper steak and bell peppers over steamed white rice. Garnish with fresh cilantro leaves. Serve hot, with extra cracked black pepper on the side if desired.
   Look for The sauce is thick and glossy, coating the meat and peppers evenly.
   Tip For a restaurant-style presentation, mound the rice in a bowl and invert onto a plate before adding the steak.

After resting, the sauce has settled and the meat looks moist and glossy. The cilantro adds a fresh, herbal note that balances the rich sauce. Everything is ready to be spooned over steaming rice.

Common mistakes

One common mistake is lifting the lid during the 4-hour cook, which releases heat and extends cooking time. Another is adding the bell peppers too early — they'll turn mushy and lose their color.

Slicing the steak too thick can result in tough, chewy pieces, so keep the strips thin. Finally, don't skimp on the cracked pepper; it's the star of the dish.

How to tell it’s done

The steak is done when it is fork-tender and the internal temperature reads at least 145°F (63°C) in the thickest piece. Since the strips are thin, they will likely be well above that after 4 hours, which is fine.

The sauce should be glossy and thickened, clinging to the meat. The bell peppers should be crisp-tender, bright in color, and slightly softened but not limp.

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