On a large container of gallon-sized heavy duty zipper top bag combine the shallots, garlic, ginger, lemongrass, brown sugar, fish sauce, lime juice, and chili garlic sauce. Ad the chicken thighs and turn hem to coat well with the marinade. Refrigerate overnight.
Preheat the oven to 425°F. Line a rimmed baking sheet with aluminum foil and spray with nonstick cooking spray. Place the chicken on the baking sheet skin side up and roast for about 45 minutes until the chicken is cooked all the way through, with an internal temperature of 165°F.
Remove from the oven and sprinkle with the peanuts and cilantro if desired (I clearly forgot to do that in these photos. Oops).
Notes
The peanuts and cilantro are optional for a few reasons:
You may not have peanuts lying around, or someone in your family might be allergic.
Some folks really, really don’t like cilantro.
I forgot to sprinkle them on for the photo, but I did remember to sprinkle them on the Thai Cucumber salad that is shown in some of these photos, so it sort of implies that I could remember to do this, only not reliably. Also think about Vegetarian Pad Thai as a side.