Easy Zucchini Beef Stir-Fry

Ingredients

• 454 g (1 pound)flank steak or sirloin steak, thinly sliced against the grain
• 30 ml (2 tablespoons)soy sauce
• 15 ml (1 tablespoon)cornflour
• 15 ml (1 tablespoon)rice wine vinegar (or dry sherry)
• 5 ml (1 teaspoon)sesame oil
• 2.5 ml (1/2 teaspoon)ground ginger
• 1.25 ml (1/4 teaspoon)black pepper
• 2 mediumcourgettes, halved lengthways and sliced
• 1red pepper, cored, seeded and sliced
• 1/2yellow onion, thinly sliced
• 2 clovesgarlic, minced
• 15 ml (1 tablespoon)vegetable oil (or avocado oil)
• 30 ml (2 tablespoons)soy sauce (or tamari for gluten-free)
• 15 ml (1 tablespoon)oyster sauce (optional, adds depth of flavour)
• 15 ml (1 tablespoon)hoisin sauce
• 5 ml (1 teaspoon)sesame oil
• 2.5 ml (1/2 teaspoon)red pepper flakes (optional, for heat)
• 60 ml (1/4 cup)water or chicken stock
• 15 ml (1 tablespoon)cornflour (for thickening)
• To garnish, optionalsesame seeds
• To garnish, optionalchopped spring onions
• For servingcooked rice or noodles

Instructions

1. 1

   Mix the marinade

   In a medium bowl, whisk together the soy sauce, 15 ml (1 tablespoon) cornflour, rice wine vinegar, 5 ml (1 teaspoon) sesame oil, ginger and black pepper.

2. 2

   Coat the beef

   Add the sliced beef to the marinade and toss so it is evenly coated.

3. 3

   Marinate the beef

   Leave the beef to marinate for at least 15 minutes, or refrigerate it for up to 30 minutes.

4. 4

   Prepare the vegetables

   While the beef marinates, slice the courgettes, red pepper and onion, and mince the garlic.

5. 5

   Heat the pan

   Heat the vegetable oil in a large frying pan or wok over high heat.

6. 6

   Add the beef

   Arrange the marinated beef in a single layer in the hot pan, cooking in batches if needed to avoid overcrowding.

7. 7

   Brown the beef

   Stir-fry for 2–3 minutes, until browned on all sides and cooked through. Remove the beef from the pan and set it aside.

8. 8

   Stir-fry vegetables

   Add the courgettes, red pepper and onion to the pan. Stir-fry for 3–5 minutes, until tender-crisp.

9. 9

   Add garlic and chilli

   Add the minced garlic and red pepper flakes, if using. Stir-fry for another 30 seconds, until fragrant.

10. 10

    Whisk the sauce

    In a small bowl, whisk together the soy sauce, oyster sauce if using, hoisin sauce, 5 ml (1 teaspoon) sesame oil, water or chicken stock, and 15 ml (1 tablespoon) cornflour.

11. 11

    Thicken the sauce

    Pour the sauce over the vegetables and bring it to a simmer. Cook for 1–2 minutes, until it has thickened slightly.

12. 12

    Return the beef

    Add the cooked beef back to the pan and toss it with the sauce.

13. 13

    Heat through

    Heat the mixture through, then remove the pan from the heat.

14. 14

    Add the garnish

    Scatter over sesame seeds and chopped spring onions, if desired.

15. 15

    Serve straight away

    Serve immediately over rice, noodles or cauliflower rice.

What is zucchini beef stir-fry?

Stir-frying cooks small pieces of food quickly in a hot pan, a technique used in many Asian cuisines. This version brings together beef, courgette and pepper with a soy-based sauce.

The method works by cooking the beef and vegetables separately before bringing them together in the sauce. That helps the meat brown and keeps the vegetables from turning too soft.

Nutrition and macros by portion

The nutrition label shows one serving as written: 450 calories, 0g protein, 0g carbs, 0g fat.

The beef provides most of the protein, while rice or noodles supply much of the meal’s carbohydrate; the oils and sauces contribute fat. Serve with a generous share of the vegetables alongside a measured portion of rice or noodles to balance the plate.

Choose and slice the beef

Cut of beef: Flank or sirloin steak both suit a quick stir-fry. Slice thinly against the grain so the pieces are easier to bite.

Marinade: Soy, vinegar, sesame oil, ginger and pepper flavour the beef, while cornflour coats it. Give it at least 15 minutes to marinate, or up to 30 minutes in the fridge.

Keep the pan hot

High heat: Start with a properly heated pan so the beef can brown rather than slowly releasing moisture. Cook in batches if the pieces will not fit in one layer.

Separate stages: Set the browned beef aside while the vegetables cook. This gives the courgettes, pepper and onion room in the pan.

Aim for tender-crisp vegetables

Vegetable timing: Stir-fry the courgette, pepper and onion for 3–5 minutes, checking for tenderness while they still have some bite.

Garlic cue: Add the garlic and optional chilli after the other vegetables, then cook for just 30 seconds, until fragrant. Adding them later helps prevent the garlic from burning.

Get the sauce consistency right

Cornflour: Whisk it thoroughly into the sauce mixture before pouring it into the pan. This helps it thicken evenly as it simmers.

Finish: Simmer the sauce for 1–2 minutes, until slightly thickened, then return the beef and toss to coat. Take the pan off the heat once everything is warmed through.

What to serve alongside

Rice or noodles: Serve the stir-fry over cooked rice or noodles to catch the savoury sauce. Cauliflower rice is another serving option listed for this dish.

Garnish: Sesame seeds and chopped spring onions add a final topping if you want to use them. Add them just before serving.

Recipe notes & tips

• Slice the beef thinly against the grain for more tender bites.
• Pat the sliced beef dry if it is very wet before adding it to the marinade.
• Keep the beef in a single layer and cook it in batches if necessary.
• Whisk the sauce again just before adding it, as cornflour can settle.
• Have the vegetables and sauce ingredients ready before heating the pan.

Variations

• Use tamari: Replace the soy sauce with tamari for the stated gluten-free option.
• Switch the cooking oil: Use avocado oil instead of vegetable oil.
• Add heat: Include the red pepper flakes for a spicier finish.
• Skip the oyster sauce: Leave it out for a less deeply savoury sauce.
• Choose your base: Serve the stir-fry over rice, noodles or cauliflower rice.

Common mistakes to avoid

• Crowding the pan: The beef can steam instead of browning, so cook it in batches.
• Overcooking the courgette: It can lose its bite, so check it within the 3–5 minute cooking time.
• Burning the garlic: Add it after the vegetables and stir-fry for only 30 seconds.
• Lumpy sauce: Whisk the cornflour fully into the liquid ingredients before adding them to the pan.
• Skipping the grain direction: Slice against the grain to make the beef easier to chew.

How to store

Refrigerate leftovers in a covered container and use within 3 days. Reheat in a frying pan over medium heat until hot throughout, adding a small splash of water if the sauce has thickened too much.

Frequently asked questions