In a mixing bowl, combine the seasoned salt, garlic powder, paprika, and ground black pepper. Apply about 3/4 teaspoon of this spice blend to each pork chop. Coat the pork chops thoroughly in self-rising flour, reserving the excess flour and seasoning mix for later use.

Heat the vegetable oil in a heavy-bottomed skillet over medium-high heat. Place the pork chops in the skillet and sear each side until browned, which typically takes about 3 minutes per side. Remove the chops from the skillet, place them on a plate, and cover them with a paper towel. Keep the drippings in the skillet for the next step.

Reduce the heat to medium and add the sliced onion to the skillet. Stir and cook until the onion begins to caramelize, approximately 5–10 minutes. Incorporate the sliced mushrooms, reserved flour, and spice mix into the skillet, adding a teaspoon of water if necessary to maintain moisture. Stir continuously until the onion mixture reaches a rich, golden brown, which should take about 5 minutes.

Gradually pour in 2 cups of water while stirring to create a smooth gravy. Bring the mixture to a boil, then reduce the heat to a simmer. Return the pork chops to the skillet, ensuring they are submerged in the gravy. Cover the skillet and let it simmer for approximately 1 hour, or until the pork chops are tender. The internal temperature of the pork should reach at least 145°F (63°C) to ensure proper cooking.