Heat oil in a pot set over medium-high. Add onion and red pepper and cook 2 minutes. Mix in rice and garlic. Add the stock and bring to a boil. Once it boils, cover rice and turn the heat to its lowest setting. Cook 15 minutes, or until the rice is tender.
Fluff the rice with a fork, and then mix in the asparagus, cilantro or parsley, salt and pepper. Let the asparagus heat through a minute or so before serving.
Note: To blanch asparagus, cook in boiling water 1 minute. Cool in ice-cold water and drain well.