Cook the pasta as per the packet directions, drain and set aside

Roughly chop the cauliflower, peel the courgette/zucchini, roughy chop and steam with the cauliflower until tender

While the cauliflower is cooking start on the roux sauce (white sauce). 

Heat butter/oil in a saucepan

Add onion and bacon and sauté until onion softened and translucent 

Add the flour and cook for around 2mins whilst stirring

Gradually add the milk (I find if you preheat the milk first, which you can do in the microwave, you will get a smoother sauce and the sauce will thicken much more quickly)

Bring the sauce just to the boil then reduce the heat. At this point you should have quite a thick but smooth sauce

Stir in ¾ Cup of the grated cheese, it should melt through the sauce, remove from heat

Once the cauliflower and courgette is tender, drain, then puree. I usually use a whizz stick/stick blender. You will end up with around 2  cups of vegetable puree,

Stir the vegetable puree into your cheese your sauce

Combine your sauce with the pasta

Then pour the pasta and sauce mixture into a greased oven proof dish. You can top with the remaining grated cheese

Bake for around 20mins at 180 degrees celsius, until the cheese on top is melted, bubbling and golden

Serve