This keto beef stir fry keeps things simple: tender beef, crisp low-carb veggies, and a bold, savory sauce that doesn’t spike your carbs. It’s quick enough for a weeknight and filling enough to power you through the day. You’ll get big flavor with minimal ingredients and only a few minutes on the stove.
If you’re looking for a meal that supports fat burning while tasting like takeout, this one’s a win. No fuss, no fluff—just a reliable go-to that hits the spot.
What Makes This Special
- Low-carb and high-fat balanced: The sauce and stir-fry fats keep carbs low while supporting ketosis.
- Quick cooking time: From pan to plate in about 20 minutes, with very little prep.
- Restaurant-style flavor without sugar: A clean, keto-friendly sauce—no cornstarch or hidden syrups.
- Flexible veggies: Use what you have as long as it’s low-carb and cooks fast.
- Meal-prep friendly: Reheats well without getting soggy when stored properly.
What You’ll Need
- 1 pound (450 g) flank steak or sirloin, thinly sliced against the grain
- 2 tablespoons avocado oil (or coconut oil/ghee)
- 1 small zucchini, halved and sliced
- 1 cup broccoli florets (small bite-size pieces)
- 1 red bell pepper, thinly sliced
- 3 cloves garlic, minced
- 1 teaspoon fresh ginger, grated (or 1/2 teaspoon ground)
- 2 green onions, sliced (whites and greens separated)
- 1 tablespoon sesame seeds (optional, for garnish)
For the Sauce:
- 3 tablespoons tamari or coconut aminos (low-sodium if preferred)
- 1 tablespoon rice vinegar (unseasoned)
- 1 tablespoon toasted sesame oil
- 1 teaspoon fish sauce (optional, for umami)
- 1/2 teaspoon red pepper flakes (adjust to taste)
- 1/2 teaspoon garlic powder
- 1/4 teaspoon black pepper
- 1/2 teaspoon powdered erythritol or monk fruit (optional, balances saltiness)
Step-by-Step Instructions
- Prep the beef: Freeze the steak for 20 minutes so it firms up, then slice thinly against the grain. Pat dry with paper towels for better browning.
- Mix the sauce: In a small bowl, whisk tamari/coconut aminos, rice vinegar, sesame oil, fish sauce, red pepper flakes, garlic powder, black pepper, and sweetener (if using).
Set aside.
- Heat the pan: Use a large skillet or wok over medium-high heat. Add 1 tablespoon avocado oil and swirl to coat.
- Sear the beef: Add half the beef in a single layer. Cook 1–2 minutes per side until browned but not overdone.
Remove to a plate. Repeat with remaining beef.
- Cook the veggies: Add remaining 1 tablespoon oil to the pan. Toss in broccoli and zucchini.
Stir-fry 2–3 minutes until crisp-tender.
- Add aromatics: Stir in garlic, ginger, and the white parts of the green onions. Cook 30–45 seconds until fragrant.
- Combine and sauce: Return the beef to the pan. Pour in the sauce and toss.
Cook 1–2 minutes to warm through and coat everything.
- Finish and serve: Remove from heat. Top with green onion tops and sesame seeds. Taste and adjust salt, pepper, or heat as needed.
How to Store
- Fridge: Store in an airtight container for up to 3–4 days.
- Reheat: Warm in a skillet over medium heat with a splash of water or broth.
Avoid microwaving too long to prevent rubbery beef.
- Freezer: Freeze in portions for up to 2 months. Thaw overnight in the fridge, then reheat gently in a pan.
Why This Is Good for You
- Keto-friendly macros: Low-carb veggies and a savory sauce keep net carbs low, supporting ketosis and fat burning.
- High-quality protein: Beef provides iron, B vitamins, and amino acids to maintain muscle while losing fat.
- Healthy fats:</-strong> Avocado oil and sesame oil help with satiety and steady energy.
- Blood sugar support: No added sugars or starches, which helps avoid cravings and energy crashes.
What Not to Do
- Don’t overcrowd the pan: Crowding steams the beef and makes it tough. Cook in batches for a good sear.
- Don’t overcook the veggies: Keep them crisp-tender.
Mushy veggies don’t reheat well and taste flat.
- Don’t add sugary sauces: Skip bottled stir-fry sauces with starches or sugar. Use the simple sauce here.
- Don’t slice with the grain: Always cut beef against the grain for tenderness.
- Don’t skip drying the beef: Moisture prevents browning, which is where the flavor is.
Variations You Can Try
- Spicy garlic beef: Add extra red pepper flakes or a teaspoon of chili crisp (check labels for carbs).
- Mushroom umami: Swap zucchini for sliced mushrooms and a splash more tamari.
- Thai-inspired: Add lime juice, fresh basil, and a tiny pinch of granulated sweetener.
- Sesame crunch: Stir in shredded cabbage and an extra drizzle of sesame oil at the end.
- Extra fat boost: Finish with a spoon of grass-fed butter for richness and satiety.
- Swap the protein: Use chicken thighs, pork tenderloin, or shrimp. Adjust cooking time accordingly.
FAQ
Is this recipe truly keto?
Yes.
It avoids sugar, cornstarch, and high-carb sauces. The veggies are low-carb, and the fats support ketosis. Track your portion sizes to stay within your daily carb limit.
What’s the best cut of beef for stir fry?
Flank steak, sirloin, or ribeye work well.
Slice thinly against the grain and cook hot and fast to keep it tender.
Can I thicken the sauce without cornstarch?
You can reduce the sauce by simmering briefly, or whisk in a small pinch of xanthan gum at the end. Start with 1/8 teaspoon and stir well.
What can I serve this with on keto?
Cauliflower rice, shirataki noodles, or a simple side salad. You can also eat it on its own for a lower-calorie, high-protein option.
How spicy is it?
Mild to medium.
Adjust red pepper flakes to your heat preference or leave them out entirely.
Can I meal prep this?
Absolutely. Portion into containers with cauliflower rice. Reheat gently to avoid overcooking the beef.
Do I need a wok?
No.
A large, heavy skillet works great. The key is high heat and not crowding the pan.
In Conclusion
Keto Beef Stir Fry for Fast Fat Burning is exactly what a busy week calls for: fast, flavorful, and aligned with your goals. With simple ingredients and a clean sauce, you’ll get restaurant-level satisfaction without the carbs.
Keep this one in your rotation for an easy win—great taste, steady energy, and zero hassle.
Ingredients
Method
- Prep the beef: Freeze the steak for 20 minutes so it firms up, then slice thinly against the grain. Pat dry with paper towels for better browning.
- Mix the sauce: In a small bowl, whisk tamari/coconut aminos, rice vinegar, sesame oil, fish sauce, red pepper flakes, garlic powder, black pepper, and sweetener (if using). Set aside.
- Heat the pan: Use a large skillet or wok over medium-high heat. Add 1 tablespoon avocado oil and swirl to coat.
- Sear the beef: Add half the beef in a single layer. Cook 1–2 minutes per side until browned but not overdone. Remove to a plate. Repeat with remaining beef.
- Cook the veggies: Add remaining 1 tablespoon oil to the pan. Toss in broccoli and zucchini. Stir-fry 2–3 minutes until crisp-tender.
- Add aromatics: Stir in garlic, ginger, and the white parts of the green onions. Cook 30–45 seconds until fragrant.
- Combine and sauce: Return the beef to the pan. Pour in the sauce and toss. Cook 1–2 minutes to warm through and coat everything.
- Finish and serve: Remove from heat. Top with green onion tops and sesame seeds. Taste and adjust salt, pepper, or heat as needed.
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