1) Peel the stalk of the broccoli, remove the florets and cut into 2.5-cm pieces. Cut the stalk in half crosswise and then slice each half into 0.5-cm thick slices lengthwise.
2) Place the stalk pieces in the bottom of a 3 litre saucepan, add the water and salt. Lay the florets on top. Cover, place over high heat and cook for 3 minutes. Decrease the heat to low and cook for an additional 3 minutes.
3) Remove from the heat, add the butter and stir to combine; serve immediately.