In a large, deep skillet, heat oil over medium-high heat. Add garlic and red pepper flakes; saute 30 seconds. Add broccoli, water, lemon juice and lemon zest; mix well. Cover skillet and cook over medium heat 8 minutes, until broccoli is crisp-tender. Season to taste with salt and pepper. Transfer broccoli to a serving dish and sprinkle with parmesan.