Slow-cooker Mongolian beef roast

Ingredients

• 650 g (1½ lb)beef roasting joint (thick rib, brisket, flank, chuck or topside)
• 2 mediumonions, coarsely chopped and separated into petals
• 2–3 tbsp, plus extra for thickening the saucecornflour
• 2 clovesgarlic, minced, or from a jar
• ½ tspground ginger, or 2.5 cm (1 in) fresh ginger, grated
• 240 mlbeef or vegetable stock
• 2 tbspdark brown sugar
• 1 tbsprice wine vinegar
• 120 ml (½ cup)reduced-salt soy sauce
• To taste, optionaldried chilli flakes
• 1–2 tbspsunflower oil
• 1 tbspcornflour, for the sauce slurry
• 2 tbspwater, for the sauce slurry

Instructions

1. 1

   Coat the beef

   Coat the beef joint all over with the cornflour.

2. 2

   Brown the joint

   Heat the sunflower oil in a frying pan. Brown the beef on all sides, using tongs to hold it steady as needed.

3. 3

   Layer the cooker

   Chop the onions coarsely and arrange them in the base of the slow cooker. Set the browned beef on top.

4. 4

   Mix the sauce

   Combine the stock, garlic, ginger, brown sugar, vinegar, soy sauce and chilli flakes, if using. Stir until the sugar dissolves, then pour the mixture over the beef.

5. 5

   Slow-cook the beef

   Cook on Low for 5–6 hours, Medium for 4–5 hours or High for 3–4 hours.

6. 6

   Thicken the gravy

   When the beef is cooked, pour all the cooking liquid into a saucepan and bring it to the boil. Mix 1 tablespoon cornflour with 2 tablespoons water. Slowly drizzle the slurry into the boiling liquid, stirring continuously, until the gravy thickens; you may not need all of it.

7. 7

   Slice and serve

   Slice the beef and arrange it over white rice. Pour over the gravy and serve with a fresh green salad and steamed vegetables.

What is Mongolian beef?

Mongolian beef is commonly associated with Chinese-American restaurant cooking, where thin slices of beef are stir-fried with a savoury-sweet soy-based sauce. This version borrows those familiar flavours but cooks a whole joint slowly instead.

Slow cooking gives the gravy time to flavour the beef, while browning the joint first adds colour and savoury depth. Slicing it to serve makes the dish easy to pair with rice and vegetables.

Nutrition and macros by portion

The nutrition label shows one serving as written: 303 calories, 41g protein, 17g carbs, 7g fat.

The beef provides most of the protein and some of the fat, while the brown sugar and cornflour contribute carbohydrates; the soy-based gravy also adds sodium. Serve with a generous portion of steamed vegetables alongside the rice to balance the plate.

Choosing the beef

Joint choice: The recipe allows thick rib, brisket, flank, chuck or topside. The key is to use a whole roasting joint that fits your slow cooker and cook it for the time specified for your setting.

Cornflour coating: A light coating goes on before browning. It helps form a surface layer on the beef, while extra cornflour is reserved to thicken the finished gravy.

Building the flavour

Aromatics: Garlic and ginger bring warmth to the stock-based sauce. Ground ginger is convenient, while grated fresh ginger gives you another option from the recipe.

Sweet and savoury: Soy sauce, brown sugar and rice wine vinegar balance one another in the cooking liquid. Add chilli flakes only if you want a little heat.

Browning and layering

Browning: Turn the joint so each side colours in the hot oil, holding it with tongs as necessary. This step happens in a frying pan before the beef goes into the slow cooker.

Onion base: Spread the onion petals across the bottom of the cooker, then place the beef on top. Pour the mixed stock over the joint so the cooking liquid can flavour the meat and onions.

Getting the gravy right

Reduce the risk of lumps by mixing the cornflour with water before adding it to the cooking liquid. Pour the slurry in gradually while stirring continuously.

Stop when the gravy reaches the thickness you want; the method notes that you may not need all the slurry. If it becomes too thick, stir in a little water.

Checking the timing

The cooking time depends on the slow-cooker setting: allow 5–6 hours on Low, 4–5 hours on Medium or 3–4 hours on High. The recipe does not give a separate doneness temperature, so use the stated times and check that the joint is cooked before slicing.

The gravy is thickened separately after the beef has cooked. Set aside time for this final stovetop step before serving.

Serving the roast

The recipe suggests serving sliced beef on white rice, with the gravy poured over the top. A fresh green salad and a bowl of steamed vegetables round out the meal.

For neat slices, let the joint rest briefly after removing it from the cooker, then cut across the grain where it is visible.

Recipe notes & tips

• Use tongs to steady the joint while browning each side.
• Stir the sauce ingredients until the brown sugar has dissolved before pouring them into the cooker.
• Add chilli flakes to taste, or leave them out for a milder gravy.
• Mix the cornflour with water smoothly before adding it to the hot cooking liquid.
• Add the slurry gradually and stop once the gravy is thick enough for serving.

Variations

• Fresh ginger: Use grated fresh ginger instead of the ground ginger.
• Vegetable stock: Choose vegetable stock instead of beef stock for the cooking liquid.
• More heat: Add extra chilli flakes to the sauce to suit your taste.
• Milder gravy: Omit the optional chilli flakes.
• Alternative joint: Choose another listed cut, such as chuck, brisket or topside.

Common mistakes to avoid

• Skipping the browning: Brown the joint on all sides in the frying pan before slow-cooking it.
• Adding dry cornflour: Mix it with the water first to make a slurry.
• Pouring in the slurry all at once: Add it slowly while stirring and stop when the gravy thickens.
• Over-thickening the gravy: You may not need all of the cornflour mixture.
• Guessing the setting time: Follow the specified 5–6 hours on Low, 4–5 on Medium or 3–4 on High.

How to store

Refrigerate leftover beef and gravy in a covered container and use within 3 days. Reheat until piping hot, adding a splash of water if the gravy has thickened in storage.

Frequently asked questions