Heat 1 TBSP of the oil in a large saute pan over medium-high heat.
Add the HALF the pork to the pan and cook until browned, about 5 minutes.
Transfer the pork to a plate and set aside then add the remaining 1 TBSP of oil to the pan and cook the remaining pork.
Transfer that cooked pork to the plate with the other cooked pork and set aside.
Add the onion to the pan and cook, stirring often, until the onion softens, about 5 minutes.
Stir in 1 tsp salt, 1 tsp black pepper, and the flour until well combined.
Stir in the vinegar and water then use a wooden spoon or spatula to scrape any stuck on bits from the bottom of the pan.
Add the pork back into the pan along with the bay leaves and bring to a boil.
Reduce the heat to medium-low and simmer, stirring occasionally, about 15 minutes.
Increase the heat to medium-high and cook, stirring often, until the sauce is thickened, 10 to 15 more minutes.
Take the pan off the heat and season with salt & pepper to taste.
