1) Set up a steamer. Steam the broccoli florets for 3 to 5 minutes, until just slightly tender.
2) In a separate small saucepan, heat the orange juice over medium-high heat. Reduce to 60ml. Remove juice from heat and add butter, stirring to melt and combine thoroughly.
3) Pour over the blanched broccoli and toss. Serve with the orange zest over the final served dish.