Clean the pork, let it drain, and cut it into bite-sized cubes. Add 2 tablespoons fish sauce, 1 teaspoon sugar, and 1/3 teaspoon pepper to the pork. Mix all the ingredients well and marinate for 15 minutes to absorb the flavors.

Finely chop 3 shallots, slice 3 shallots thinly. Mince the garlic and red chili pepper. Toast the white sesame seeds until golden. Dissolve 2 tablespoons sugar in a bowl of water.

Add 1 tablespoon annatto oil to a pan. When the oil is hot, sauté the chopped shallots, garlic, and chili until fragrant, then pour in the sugar water and cook until it thickens. Turn off the heat and let it cool.

In another pan, add 2 tablespoons cooking oil. When the oil is hot, sauté the sliced shallots until fragrant, then add the marinated pork and stir-fry until the pork is firm. Continue to stir-fry until the marinade is absorbed into the pork.

Next, pour the sugar sauce over the pork and cook over medium heat until the sauce thickens. Add 1 tablespoon chili sauce and the juice of 1 lemon, and continue to stir until the sauce evenly coats the pork and is absorbed.

Season the sweet and sour sauce to taste according to your family's preference. Add the toasted sesame seeds and stir well, then turn off the heat.

Serve the sweet and sour pork on a plate with hot rice.