Add peanut oil to a wok and place on medium heat. Cut the pork belly into bite-sized pieces and place in the wok.
Mix together the garlic, soy sauce, masala powder, red curry paste, sugar and fish sauce; add to wok and stir. Add 1 cup water and 1/2 chicken stock; increase heat, bring to a light boil and stir for 5 minutes. Add the rest of the water and chicken stock; bring to a boil again. Simmer for 3 to 4 minutes.
Add the tamarind juice and season to taste. Add peanuts and ginger, cooking until sauce thickens to desired consistency.