Preheat the oven to 425 degrees Fahrenheit and lightly grease a baking dish or sheet pan.
Pat the chicken breasts dry with paper towels, then pound the thicker ends lightly so the pieces are more even in thickness.
Rub the chicken breasts all over with the olive oil.
In a small bowl, mix the salt, black pepper, garlic powder, onion powder, paprika, oregano, and thyme, then sprinkle the seasoning evenly over both sides of the chicken.
Arrange the chicken breasts in the prepared baking dish or on the sheet pan in a single layer.
Bake for 18 to 22 minutes, or until the thickest part of the chicken reaches 165 degrees Fahrenheit on an instant-read thermometer.
Remove the chicken from the oven and let it rest for 5 minutes before slicing.
Drizzle with the lemon juice, sprinkle with parsley if using, and serve warm.