The first step is to separate the broccoli into stems and florets. Make sure to really separate it, leaving only small florets.

Cook the mortadella in a splash of oil until it browns. Remove from pan.

Cook the onion, carrot, and broccoli stems until just starting to lightly brown, about 7-10 minutes. Add garlic.

Add the butter and when it melts add flour and mix well. Add the milk stirring well to combine with the flour. Blend this mess with a hand blender or in a normal blender. (you don't NEED to do this step but I kinda wanted the veg to be smooth and in with the sauce. I was also too lazy to cut stuff uniformly so that's another reason I had to blend it.)

Next add the broccoli florets and stir. Wait 2 minutes and start adding the grated cheeses slowly, stirring to combine. the sauce should be very liquidy.

Boil the pasta for only 2 minutes. Strain and mix with the cheese sauce. Add in mortadella. Pour into baking dish. Top with breadcrumbs and bake for about an hour at 400. If the top isn't browned at the end, broil it.