In a medium bowl, whisk together the olive oil, brown sugar, and soy sauce until the sugar is mostly dissolved. This creates the liquid base that will carry all the flavors into the chicken. The combination of oil and soy sauce ensures both fat-soluble and water-soluble flavors penetrate the meat evenly.

Add the lemon zest, garlic, smoked paprika, salt, and pepper to the marinade base and stir well to combine. Then add the parsley and thyme, mixing gently to distribute the herbs throughout. I like to add the fresh herbs last so they maintain their vibrant flavor rather than getting overpowered by the other seasonings.

Place 2 pounds of chicken thighs into a large bowl or resealable bag and pour the marinade from Step 2 over them, making sure every piece is well coated. For maximum flavor development, I recommend marinating for at least 4-6 hours, but 12-24 hours is ideal since chicken thighs are fatty and benefit from longer marinating times. Cover and refrigerate.

Remove the chicken from the refrigerator 15 minutes before cooking to bring it closer to room temperature. Cook using your preferred method—baking at 425°F for 25-30 minutes, pan-searing over medium-high heat, or grilling over medium heat until the internal temperature reaches 165°F. The marinating time means the chicken will already be flavorful and juicy, so focus on achieving nice browning for added depth.