In a large skillet, melt butter. Brown meat, a few pieces at a time. Remove from skillet as they brown. Saute zucchini in skillet 7-10 minutes. Return meat and add corn, chilies, garlic, salt, oregano and cumin. Simmer, stirring occassionally, about 12-15 minutes or until meat is tender. Stir in cheese until melted. Garnish with chopped cilantro and serve.