Heat oil in large saucepan over medium heat. Add onion; cook and stir about 5 minutes or until softened. Add garlic and cook 2 minutes longer. Add broth and broccoli and bring to boil. Reduce heat, cover and cook about 5 minutes until broccoli is tender, stirring occasionally. Remove from heat and process in blender or food processor until soup is as smooth as you like. Return to pan and stir in milk, salt and pepper. Add cheese and cook and stir over low heat until cheese is melted. Garnish with additional cheese if desired.