Heat oil over medium heat in the pressure cooker and saut° onions and garlic for 2 minutes. Stir in barbecue sauce and water and simmer 5 minutes.
Add spare ribs and close pressure cooker lid. Bring to high pressure and cook for 18 minutes. Release pressure using the cold water release method.
Remove ribs from the cooker and transfer to an oiled broiler rack. Season with salt and pepper. Position broiler pan 6 inches from source of heat. Broil lightly on one side and remove from oven.
While ribs are broiling, boil remaining cooking liquid over medium high heat until it begins to thicken (about 5 minutes). Brush the thickened sauce over the ribs and broil for an additional 2-3 minutes. Turn over, brush sauce on and broil for 2-3 more minutes. Serve hot.
Servings: 4