In a large bowl, season chicken with salt and pepper. Then set aside.
In a small-medium bowl, mix together lemon juice, garlic, soy sauce, brown sugar and oregano. Pour ¼ cup the mixture over chicken.
(optional) Marinate chicken for 30 minutes or up to 8 hours in the refrigerator.
Heat oil in a large pan or skillet over medium-high heat. Remove chicken from the marinade and place into the hot pan. Sear it on both sides until golden brown.
Reduce heat and cover the pan with a lid. Turn the chicken every 5 minutes until it’s cooked through (about 15 minutes in total, cooking time may vary depending on the thickness of your chicken). The internal temperature should reach 165 degrees F.
Remove chicken from the pan. Add the sauce mixture and increase heat to medium-high. Cook for about 5 minutes and your sauce should have thickened slightly. (The sauce will thicken more when it cools down)
Add chicken back to the pan and coat it evenly with the sauce.
Garnish with finely chopped parsley, lemon wedges and lemon zest if desired.
Serve over rice, pasta, or potatoes with vegetables.