MARINADE: Using a mini chopper, pulverize the white part of the lemongrass. Use a knife and a cutting board if you don't have a mini chopper.
Add the shallot and garlic. Pulse until fine.
Add the lemongrass, garlic, shallot, soy sauce, fish sauce, sugar, black pepper, and oil in a bowl. Mix well.
CHICKEN DRUMSTICKS: Butterfly the chicken legs. Gently make one vertical cut down the leg, in the center, touching the bone. This cut will help open up the chicken leg.
Make a couple more cuts if needed. The chicken leg should be flat.
Combine the marinade with the chicken drumsticks and massage the marinade well.
Marinade for 30 minutes.
AIR FRY: Preheat the air fryer to 350 degrees.
Line your air fryer basket or tray with parchment paper for easy clean up.
Arrange the chicken drumstick skin side down. Spoon the rest of the marinade on top of the chicken.
Air fry the chicken at 350 degrees for 25 minutes. Flipping halfway to get a super crispy skin.
Serve with nuoc cham dipping sauce and rice.