boil broccoli florets in water, drain half the water off (keep to one side) blitz with a hand blender and add a veg stock cube - re add some of the drained off liquid if required.. add chunks of cheese and stir until melted (Cheddar will do fine, but have used others.. Crumbly Lancs was very nice for this!) season to taste..
Can add potato's and onion for variation (part cook these before adding the broccoli)