Heat the oil in a heavy medium saucepan over medium heat. Add the onions and cook for about 5 minutes. Add the garlic and cook for 1 minute. Add the chiles and cook until slightly darkened on both sides, about 1 minute.
Pour in the broth and bring to a boil. Cook until the chiles are soft, about 5 minutes. Transfer to a blender, add oregano and cumin, and season with salt and pepper. Puree until smooth.
Heat a large stovetop grill pan to medium/high heat. Divide the adobo sauce into two separate bowls. With a basting brush, brush adobo sauce all over the chicken pieces. Reserve the second bowl of adobo sauce once the chicken is cooked. Sear the chicken pieces, skin sides down, until grill marks appear about 5 minutes. Turn the chicken and transfer to a baking dish, then into the oven. Roast the chicken, basting with adobo sauce every 15 minutes. Roast for about 50 minutes or until an instant-read thermometer inserted registers an inner temperature of 180ºF.
Preparing the corn:
Heat a stovetop or outdoor grill to medium/high heat. If using the stovetop pan, I like to line my grill with easy-release foil paper. Lay the corn on the hot grill and drizzle with a little oil. Turn the corn often and it starts to brown in spots, about 10 to 15 minutes.
Lay the corn onto the serving dish, season with salt, pepper, chile Limon powder, and lime juice, and sprinkle with cilantro.
Other Toppings: Mexican crema, mayonnaise, crumbled cotija cheese or Parmesan cheese.