Heat a heavy bottomed pot that's big enough to hold all the chicken in a single layer over medium high heat until it's hot. Pat the chicken thighs dry with a paper towel and sprinkle generously with salt and pepper. Place the chicken skin side down and let some fat render out of the skin. Continue frying undisturbed until the skin is brown and crispy. Flip the thighs over and brown the second side

Transfer the chicken to a plate then quickly add the garlic, ginger and garam masala and stir to distribute in the oil. You want it just long enough to caramelize the garlic and ginger, but not long enough to burn it. Since the garam masala is brown it's a bit tricky to tell when it's done, but I've found that the mixture gets sticky when the sugars in the garlic and ginger have caramelized. By this point this mixture will be very fragrant and it's where this curry gets its base layer of flavor from to fry

Add the onions and lemongrass to the mixture and fry, stirring occasionally until it's reduced to about its original volume and takes on a sticky texture (this could take as long as 40 minutes). The caramelized onions give the curry sweetness and depth. By cutting the onion thin, they caramelize faster and by cutting them against the grain (rings), the onions will dissolve into the sauce ¼

Add the remaining ingredients and return the chicken to the pot. Cover with a lid and bring to a boil. Turn down the heat and cook at a gentle simmer for about an hour, or until the chicken is very tender and falls off the bone

Garnish with something green (such as cilantro or scallions) and serve with coconut milk rice