Heat oven to 425 degrees. Lay pancetta in a roasting pan 9×13) and put on top shelf.
quarter the cauliflower, put in saucepan with macaroni on high heat, add boiling water. season with salt and olive oil. cook according to package instructions.
grate cheese. take out panceta and chop along with bread and rosemary.
drain pasta/cauliflower into bowl. Ass 1 2/3 cup of pasta water back into the roasting pan that cooked the pancetta. chop garlic, add into creme fraiche along with cheddar. Mash cauliflower a bit and add it all together.
put on top shelf of oven for8 min or until golden and bubbling. Serve Eat.