Ahoy thar Riku!
Firstly let me shake you warmly by the hand (internet-stylee of course) for confronting such a big fear. A bowl of pasta is as normal as norman to most people but for a lot of ED sufferers (I'd be willing to be almost all ED sufferers actually) it's a massively scary premise, so to have done what you did is seriously amazing. Please be proud of it
Do you think that perhaps you're focusing on the cheese, fat, potential health consequences etc, etc, as a means of deferring some of the panic and anxiety that inevitably happens when you challenge your ED? It seems you've got your head raging in a loop when possibly, if you take a step back for a moment, you might realise that you're obsessing over something that was
fabricated/excaberated by the ED to derail you. These are just my musings though, obviously I'm not in your head and I don't have mystical powers (..yet), so feel free to tell me off if I'm wrong.
Maybe you're getting so anxious because you weren't quite ready for such a challenge. I'm all for pushing yourself as hard as you can (in my experience the baby-steps approach ends up in my version of the stationary approach, concluding in the backwards-into-ED-silliness approach), but maybe you could start off by having just a bit of cheese a week until you get more used to it and more comfortable with the idea of eating it. Sometimes when we're desperate for recovery, for a LIFE, we throw ourselves head-on at our biggest fears in the hope that enough gusto and forcing will get us to our goal quicker. It usually has the opposite effect though! Keep challenging yourself, and keep in mind the bigger picture, but give yourself a break every now and then too. Recovery isn't a magical ride along a rainbow, it's hellfire! But you'll get there, oh yes indeed you will.
While I'm rambling, I have an extra piece of "advice" (you will understand the quotation marks when you read how lame it is) for you all. After eating something your ED wasn't entirely happy about, if you start freaking out/getting in a tiz/crying and shaking in the corner etc, try this: stand up immediately and DO A SHIMMY. Or a jig if you'd prefer....a bop, even. I SWEAR it helps (honest, I'm not just saying this as a feeble attempt at humour, it WORKS I tell you!), it clears the head, gets some endorphins going, and suddenly you find yourself wondering what all the fuss was about. I'm shoulder-shimmying right now actually. It feels fantastic.
P.S. I didn't quite make my goal of 5 lb increase before uni restarted, but I'm working on getting more protein in my diet (musclesss) and I WILL get there!