Cut the upper two things of the lemongrass stalks (if applicable, remove leaves). Remove outer layer of lower third. Mince the rest into very small pieces. Mince the shallot and garlic. Mix everything but the chicken together to obtain the marinade.
Cut the chicken into medium pieces (think skewers). Then put pieces in marinade and leave to marinate in fridge for at least 2 hours (overnight if possible).
Grill until cooked.
Or heat up a wok on a stove on medium heat; put a dash of oil, the chicken and marinade in the wok, and cook covered until the chicken is done. Then crank the heat up and wait for the marinade to caramelise, turning the chicken so that it is coated in caramelised marinade.
Serve with rice and with a tart/fresh vegetable (tomatoes, broccoli...).
Recipe by Aliette de Bodard at https://www.aliettedebodard.com/recipes/dui-ga-sa-lemongrass-chicken-thighs/