Season pork chops all over with salt and pepper.

In a shallow dish, mix together flour with garlic powder and chili powder. Coat pork chops in flour, shaking off excess. Reserve 2 tablespoons seasoned flour.

In a large, heavy skillet over medium heat, heat ¼ cup oil until shimmering. In batches, cook pork chops until golden, 4-5 minutes per side. Transfer to plate. Wipe out skillet.

Reduce heat to medium low, pour in remaining oil, and add onions. Season with more salt and pepper and cook until very soft and slightly caramelized, 15-20 minutes. Add butter and let melt, then sprinkle in reserved flour. Cook until flour is no longer raw, about a minute. Stir in chicken broth and heavy cream and bring to a simmer, until sauce begins to thicken, about 5 minutes.

Return pork chops to skillet and cook until pork is cooked through, about 10 minutes more.

Garnish with parsley and serve immediately.