In a small bowl, whisk together garlic powder, paprika, onion powder, salt, dried oregano, and black pepper.
Place the chicken tenderloins in a mixing bowl and pour the seasoning over them; toss until each piece is evenly coated.
Heat the olive oil in a skillet over medium-high heat until shimmering.
Add the seasoned tenderloins to the hot skillet in a single layer and cook, turning as needed, until golden brown and an instant-read thermometer inserted into the thickest part reads 165°F (about 6–7 minutes total).
Transfer to a plate and serve immediately; sprinkle with fresh parsley if desired.