After preparing the pork belly, heat a pan to medium heat (I aim for 4.5/10 heat on my stainless steel pot). Wait for pan to heat to temp. Add oil, or the pork fat, and add the pork belly cubes after. Heat slightly covered for 6-8 minutes, waiting for it to brown.
After the pork belly has browned, add your shallots. Cook slightly covered again for 2 minutes, or until shallots have browned. Add garlic, and heat for about a minute. Stir fry. Add the rock sugar and wait for that to melt into the mixture. Stir.
Add shaoxing wine to begin deglazing the pan. Next add your soy sauce, and water. Add star anise, and cinnamon stick (or powder).
Bring to a boil, and then lower to a simmer, pan uncovered. I'd simmer until the sauce reduces down to desired consistency. It should be not be too thick, just slightly thick, glossy, but still pourable. Depending on the simmer heat levels, this can take about 20-40 minutes. The longer you go, the more water you'll need, but the pork will be more braised and savoury as a result. Remove star anise before serving.