Drain the pickled jalapeños, reserving the brine. Combine the jalapeños, reserved brine, and fresh lime juice in a bowl or large resealable bag. Add the chicken thighs, ensuring they're fully submerged in the marinade. Cover or seal, then refrigerate for at least 4 hours, preferably up to 12 hours. This extended marinating time allows the flavors to deeply penetrate the chicken while the acid from the brine and lime juice helps tenderize the meat.

Remove the chicken from the marinade and pat it completely dry with paper towels—this is crucial for achieving proper browning in the pan. Reserve the marinated jalapeños separately. In a small bowl, combine the smoked paprika, ancho chile, onion powder, garlic powder, ground cumin, black pepper, sea salt, and dried Mexican oregano. I like to whisk these spices together first so they distribute evenly when coating the chicken, rather than just sprinkling them on randomly.

Place the dried chicken thighs in a bowl and sprinkle the spice blend evenly over all sides, tossing gently to coat thoroughly. Let the seasoned chicken rest at room temperature for 15 minutes. This resting period allows the spice flavors to begin adhering to the chicken and creates a better crust when cooking.

Heat the grapeseed oil in a large skillet over medium-high heat until it shimmers. Once hot, carefully place the chicken thighs in the pan and sear without moving them for 5-6 minutes until the bottom develops a golden-brown crust. Flip each thigh and cook for another 5-7 minutes on the other side. Continue cooking, turning occasionally, until the internal temperature reaches 165°F when measured with a meat thermometer at the thickest part. I find that medium-high heat gives you that beautiful crust while the lower temperature of the thighs prevents them from drying out—just watch them closely to avoid burning.

Transfer the cooked chicken to a clean plate and tent loosely with foil to keep warm. Return the skillet to medium-high heat and add the reserved marinated jalapeños from Step 1. Cook, stirring occasionally, for 4-5 minutes until the peppers are slightly charred and heated through to 165°F. Let the chicken rest on its plate for 5 minutes—this allows the juices to redistribute throughout the meat, keeping it moist and tender when you cut into it.

Arrange the rested chicken thighs on a serving platter and top or arrange the charred pan-roasted jalapeños alongside them. Drizzle any pan juices over the chicken for added flavor and moisture. Serve immediately with your choice of sides such as rice, roasted vegetables, or fresh salsa.