Place the pork chops in a pan, and marinate with salt, pepper, garlic, oregano,
cumin, and sour-orange juice. Arrange the slices of onions on top. Cover, and
refrigerate for at least 2 hours, preferably overnight. This will make the pork
chops as tender as possible.
When fully marinated, remove the chops and pat dry with paper towels.
Reserve the marinade and the sliced onion.
Heat the olive oil in a large skillet over medium-high heat. When the oil
is sizzling, add the chops one by one, and keep turning them over to brown
evenly, about 2 minutes per side. When they have browned, set them aside
on a plate. Now add the reserved onion slices to the skillet, and saute over
medium heat until translucent, about 3 minutes. Add 1/2 cup of the reserved
marinade, return the chops to the skillet, and saute for about 10 minutes,
turning once or twice, until they are cooked through and juices penetrate.
Remove to a serving platter, and spoon the onions and pan juices over them