Soak the rib tips in the water for about 1 hour. This will help largely reduce the foamy part when we cook later. Remove the ribs from the water and pap try.
Heat up a cast iron pan over medium-high heat, add 1 tbsp of cooking oil and add the ribs in. Try not to flip the ribs until one side is brown. Push the ribs to one side, and use the empty side of the pan to sautee the minced garlic and fermented black bean mixture, until releases the aroma.
Add 2 tbsp of soy sauce, 2 tbsp of oyster sauce, and 1 tbsp of sugar. Mix well everything and add about 1.5 cups of boiling water to the pan. Cover with a lid and cook for 15 minutes.
Add the green beans and mix well with the ribs. Keep cooking for another 15 minutes until the water is nearly evaporated. If there is still plenty of water remaining, turn up the heat to high and keep stirring. You can also taste it to see if it is salty enough, and add extra salt if needed.