Gather all ingredients.
Heat oil in an extra-large skillet over medium heat. Add garlic and cook until fragrant and lightly browned, about 2 minutes. Remove garlic from the skillet with a slotted spoon; discard.
Season chicken with salt and pepper. Add chicken to the skillet. Cook chicken until browned, turning once, about 16 minutes.
Add lemon juice to the skillet and season chicken with oregano. Turn chicken to coat. Continue cooking until lemon juice reduces, and chicken is 175 degrees F (80 degrees C) when tested with an instant-read thermometer, about 1 minute. Remove from heat.
In a small bowl, toss together dill and lemon zest. Stir in feta, if using.
Sprinkle herb-feta mixture over chicken and serve.