Place one chicken breast between two pieces of plastic wrap on top of a cutting board. Use a rolling pin or the smooth side of a meat mallet to pound it to ~1/3 inch thickness. Repeat with the second chicken breast. Remove the plastic wrap and cut both flattened chicken breasts in half lengthwise to create 4 equal portions.
Whisk together the salt, pepper, garlic powder, onion powder, and smoked paprika.
Season both sides of each piece of chicken evenly with the seasoning mix.
Heat the olive oil in a large, heavy-bottomed skillet over medium-high heat. Add the chicken to the pan* and sear for 3-4 minutes on either side or until a meat thermometer inserted into the thickest piece reads 165°F. Transfer the chicken to a plate and set aside.
Add the olive oil to the pan, followed by the onions. Season the onions with salt and turn the heat to medium-low. Saute the onions until they are softened and nicely caramelized. If the pan starts to get dry, add a splash or two of chicken broth or water. Repeat as needed.
Add the flour and garlic powder to the onions and cook for 30 seconds, stirring continuously. Whisk in the broth, ½ cup at a time. Keep on whisking and watch as the gravy thickens. Once thickened to your desired consistency, turn the heat off.
Taste the gravy and season with salt and pepper to taste.
Return the chicken to the pan and spoon the gravy over it.
Notes
* Don’t crowd the pan. If you need to fry the chicken in batches, do it.