In a shallow dish, combine 1/3 cup of flour with salt, pepper, garlic powder, onion powder, and smoked paprika. Dredge each pork chop in the seasoned flour, shaking off any excess. Set aside.

Heat vegetable oil in a heavy-bottomed cast iron skillet over medium-high heat. Sear the pork chops for 3 to 4 minutes per side until golden brown. Remove chops to a plate and set aside.

Reduce heat to medium. Add butter and let it melt. Add sliced onions and cook for 8 to 10 minutes, stirring occasionally until soft and golden brown.

Stir in minced garlic and cook for 1 minute, stirring constantly.

Sprinkle the remaining 3 tablespoons of flour over the onions and stir well. Cook for 1 to 2 minutes to lightly brown the flour.

Gradually pour in chicken broth, stirring continuously to prevent lumps. Add Worcestershire sauce, dried thyme, and bay leaf, and bring to a simmer.

Return pork chops to the skillet, ensuring they are covered with onion gravy. Cover with a lid and reduce heat to low.

Let simmer for 35 to 45 minutes, checking that they reach an internal temperature of 145°F.

Remove bay leaf and taste the gravy, adjusting seasoning if needed.

Spoon the gravy over pork chops and garnish with fresh parsley if desired.