HEAT oil in large skillet over medium-high heat. Add ribs; cook, turning frequently, until browned. Remove; set aside.
ADD onion to same skillet; cook over medium-high heat, stirring occasionally, for 3 to 4 minutes or until tender. Add garlic; cook for 30 seconds. Add water, tamarind paste, sugar, vinegar and bouillon. Return ribs to skillet; bring to a boil. Reduce heat to medium-low; cover.
COOK for 1 hour or until pork is tender. Remove ribs; set aside and keep warm. Boil sauce until reduced by half, skimming off fat. Add flour mixture; cook, stirring constantly, for 2 minutes or until sauce is thick. Pour sauce over ribs. Serve with rice.