Pork rib sinigang

Add a splash of veg oil to a wide, high-sided pan on medium-high heat. Add the onions and fry for 2 to 3 minutes until softened. Season the ribs with salt and pepper and add them to the pan. Sear about 2 minutes, then flip and sear about 2 minutes more. At the flip, add the garlic. As the ribs brown, move the onions and garlic around a bit so they don't burn.

Add enough stock to the pan to cover the ribs. If more liquid is needed, just top up with water. Add the bay leaves, tamarind concentrate, and fish sauce. Bring to a simmer, then turn the heat down to medium-low. After 15 minutes, skim any foam from the surface.

Add the tomatoes and jalapeno to the pan. Cover, and let simmer for 1 1/2 hrs until the meat is tender. Add water as needed to keep the ribs submerged.

Remove the bay leaves and jalapeno. Add the eggplant and turn the heat back up to medium-high. Continue simmering uncovered for 5 minutes. Add the beans and bok choy and simmer another 5 minutes. Check the seasoning and add salt and freshly cracked black pepper to taste. Take the pan off the heat and add the spinach. Give the spinach a minute to wilt, then serve the soup hot with steamed rice.