Description

Crispy-edged air fryer beef tossed in a glossy Mongolian-style sauce with garlic, ginger, and brown sugar. Big takeout flavor, lighter, faster, and built for weeknight cooking.

Ingredients

Scale

Beef

1 lb flank steak or sirloin, thinly sliced against the grain

1/2 teaspoon Kosher salt

1/4 teaspoon ground black pepper

3 Tbsp cornstarch

Sauce

1/4 cup low-sodium soy sauce

3 tablespoons brown sugar, packed

4 cloves garlic, minced

1 teaspoon grated fresh ginger

1/2 teaspoon onion powder

1 teaspoon rice vinegar

1/4 cup water or beef broth

1 teaspoon sesame oil

1 teaspoon neutral oil (avocado, canola, or grapeseed)

Pinch red pepper flakes

1 teaspoon oyster sauce (optional)

Cook Mode Prevent your screen from going dark

Instructions

Slice the flank steak in half lengthwise, then slice each piece crosswise against the grain in ¼" thick pieces and pat dry. Season lightly with kosher salt and black pepper.
Toss beef with cornstarch until evenly coated. Shake off excess so the coating stays light, and let it sit for 5 minutes.
Preheat air fryer to 400°F.
Arrange in the air fryer basket in a single layer, working in batches if needed. Lightly spray the coated beef with cooking spray.
Air fry 10–12 minutes, shaking halfway, until edges are browned and lightly crisp. I like to turn each piece over halfway through to ensure crispiness on both sides.
While the beef cooks, combine soy sauce, brown sugar, garlic, ginger, onion powder, rice vinegar, water/broth, red pepper flakes, sesame oil, neutral oil, and optional oyster sauce in a skillet over medium heat.
Bring to a boil and cook for 6-7 minutes, stirring occasionally, until the sauce has thickened.
Add cooked beef to the skillet and toss to coat. Let it bubble 60–90 seconds so the sauce clings and thickens naturally.
Taste and adjust with a splash of soy sauce or a pinch of brown sugar if needed.
Finish with sliced green onions and sesame seeds. Serve immediately.

Notes

Thin slicing matters. Cutting against the grain keeps the beef tender instead of chewy.

Let the cornstarch sit on the beef for a few minutes before cooking — this helps the coating adhere and crisp.

Halfway through cooking, I like to flip each piece of beef individually. It takes an extra minute, but it gives both sides a better sear and keeps the texture consistent. Worth it every time.

If the sauce needs thickening, whisk 1 teaspoon cornstarch with 1 teaspoon water and stir it into the simmering sauce. Let it bubble for 30–60 seconds until glossy and thickened.

The sauce is designed to coat, not pool. If serving over rice, spoon lightly from the pan.

Air fry in batches if needed. Overcrowding steams the beef instead of crisping it.

Leftovers reheat best in a skillet to restore texture — microwaving softens the coating.

Prep Time: 15 minutes
Cook Time: 12 minutes
Category: Dinner
Method: Air Fryer + Stovetop
Cuisine: Asian-inspired