Blend the aromatics: In a blender or food processor, combine the white onion, garlic cloves, and grapeseed oil. Blend until smooth.

Make the marinade: In a large bowl, combine the blended onion, garlic mixture with minced lemongrass, soy sauce, fish sauce, sugar, and black pepper.

Marinate the chicken: Add the chicken thighs to the bowl and toss to coat. Cover and marinate in the fridge for at least 30 minutes, or overnight for best flavor.

Air Fry (or grill/bake):

Air Fryer: Preheat to 380°F. Arrange the chicken in a single layer and air fry for 16–20 minutes, flipping halfway through, until golden and cooked through.

Grill: Grill over medium-high heat for 6–8 minutes per side, or until nicely charred and cooked through.

Oven: Bake at 400°F for 25–30 minutes, or until internal temp reaches 165°F.

Serve with jasmine rice, vermicelli noodles, or pickled carrots and daikon, and cucumbers. Add nuoc cham sauce on the side.