20-Minute Spicy Beef Stir Fry
This spicy beef stir fry is the kind of meal that comes together faster than you can order takeout. Thin slices of beef sear quickly in a hot pan, then get tossed with a glossy, fiery sauce and crisp vegetables.
It’s bold, savory, and just the right amount of hot. Serve it over steamed rice and dinner is on the table in about 20 minutes.
Why This Stir Fry Is a Weeknight Win
The sauce is the star: a mix of soy sauce, brown sugar, and gochujang that thickens into a sticky glaze as it hits the heat. It coats every piece of beef and vegetable without being drowning or too sweet.
I keep this one on heavy rotation because the whole thing, from slicing the beef to the final toss, takes less than half an hour. Cleanup is quick too, since everything cooks in one pan.
Ingredients
- 1 lb flank steak: thinly slice against the grain for tenderness
- 1 tbsp plus 1 tsp cornstarch: divided for coating the beef and thickening the sauce
- 3 tbsp soy sauce: low-sodium works well here
- 1 tbsp brown sugar: packed
- 1 tbsp gochujang: Korean chili paste, gives depth and heat
- 2 cloves garlic: minced
- 1 tsp grated ginger: fresh, not powdered
- 1 tbsp water: helps the sauce come together
- 1 tbsp sesame oil: for finishing, not cooking
- 1 red bell pepper: sliced into strips
- 1 small onion: sliced
- 2 green onions: sliced, for garnish
- 1 tbsp vegetable oil: for searing
- Sesame seeds: for garnish
- Steamed rice: for serving
Variations / Substitutions
- Switch the protein: Chicken breast cut into thin strips works great, just cook through.
- Sweetness swap: Use honey or maple syrup instead of brown sugar.
- Gochujang alternative: Sriracha or chili garlic sauce give a similar heat with slightly less depth.
- Add acid: A splash of rice vinegar stirred in at the end brightens the whole dish.
- More heat: A pinch of red pepper flakes in the sauce or extra gochujang.
- If you like the sound of this one, our Quick Chicken Stir Fry with Peanut Sauce is another weeknight favorite.
How to Make Spicy Beef Stir Fry
Step 1: Whisk the Sauce Together
In a small bowl, whisk 3 tbsp soy sauce, 1 tbsp brown sugar, 1 tbsp gochujang, 1 tsp cornstarch, the minced garlic, grated ginger, and 1 tbsp water until the sugar dissolves. Set it near the stove.
The cornstarch will help the sauce thicken into a glossy coating once it hits the heat. No need to marinate the beef separately with this method.
Step 2: Sear the Beef
Toss the sliced beef with 1 tbsp cornstarch and a pinch of salt until evenly coated. Heat 1 tbsp vegetable oil in a large skillet or wok over high heat until shimmering. Add the beef in a single layer, working in batches if needed, and cook for about 2 minutes without moving it.
You want a deep brown sear on the first side. Flip the pieces and cook for 1 more minute until just cooked through but still tender. Transfer the beef to a plate.
Step 3: Stir-Fry the Vegetables
Reduce the heat to medium-high. Add the sliced onion and bell pepper to the same pan. Cook, stirring often, for about 3 minutes, until the vegetables soften and the onion turns translucent in spots.
If the pan looks dry, add a small splash of water or another teaspoon of oil. You want them crisp-tender, not mushy.
Step 4: Coat the Beef in Sauce
Return the beef and any juices to the pan. Pour the sauce over everything and stir constantly for 1 to 2 minutes, until the sauce bubbles, thickens, and coats the beef and vegetables.
The sauce will turn glossy and cling to every piece. Remove the pan from the heat and drizzle the 1 tbsp sesame oil over the top, then toss once more.
Step 5: Serve Over Rice
Spoon the stir fry immediately over bowls of steamed jasmine rice. Scatter sliced green onions and sesame seeds on top.
A little extra red pepper flakes or a drizzle of sriracha on the side if you like things fierier. The rice soaks up the sauce, so don’t skip it.
Tips for the Best Spicy Beef Stir Fry
- Slice the beef when it’s still slightly frozen; it’s much easier to get thin, even slices.
- Use a large pan or wok and avoid overcrowding. Too much meat in the pan steams instead of sears.
- If you want a green vegetable, toss in broccoli florets or snap peas with the bell pepper.
- Taste the sauce before you add it to the pan. More gochujang for extra fire, or a pinch of sugar if it’s too salty.
Storing Leftovers
- Refrigerate: Store in an airtight container for up to 3 days. The sauce keeps the beef moist.
- Reheating: Warm it in a skillet over medium heat with a splash of water to loosen the sauce, or microwave briefly on medium power.
What to Serve With Spicy Beef Stir Fry
This stir fry is a full meal over rice, but a quick cucumber salad tossed with rice vinegar and a little sugar cuts the richness nicely. For a crowd, add vegetable spring rolls or a cold beer.
Frequently Asked Questions
Can I use chicken instead of beef?
Yes, slice boneless chicken breasts thinly and cook them until no longer pink, about 3 to 4 minutes per side.
How do I make this less spicy?
Cut the gochujang amount in half and add a little more soy sauce and brown sugar to balance. Leave out the red pepper flakes.
What if I don’t have gochujang?
Substitute an equal amount of sriracha or chili garlic sauce. The flavor will be slightly less deep but still plenty spicy.
Can I use frozen vegetables?
Yes, just thaw them first and pat dry so they don’t steam in the pan. Add them after the onion has softened.
Spicy Beef Stir Fry Recipe
Ingredients
Method
- In a small bowl, whisk soy sauce, brown sugar, gochujang, garlic, ginger, 1 tsp cornstarch, and water.
- Toss beef with remaining 1 tbsp cornstarch and a pinch of salt. Heat vegetable oil in a large skillet over high heat. Sear beef in a single layer 2 minutes per side; transfer to a plate.
- Reduce heat to medium-high. Add onion and bell pepper; cook, stirring often, 3 minutes.
- Return beef to pan, pour sauce over, stir constantly 1-2 minutes until thickened. Remove from heat, drizzle sesame oil.
- Serve over rice, garnished with green onions and sesame seeds.
