BelleyAche,
Which diet are you on?
I would recommend if you are not already on SCD diet, that at the very least you stay away from all dairy, wheat, gluten products for now until you gut quiets down and you're out of your flare. And then, you can always start adding back 1 food at a time, to see the result you get from that particular food.
As far as adding some good calories, have you given any thought to adding a healthy Whey Protein product like Dr. Mercola's Pro-Optimal Whey and it comes in chocolate too! You can make it with Almond milk which is very healthy and contains lots of good vitamins and add to it: L-glutamine 15 grams powder to help with colonic repair too.
Also, another thing to keep in mind, which I have found very helpful is the whole concept of food combining. If you need info on this, I've found this very helpful: http://cureforulcerativecolitis.com/step-1-methodology-to-eating
I hope you feel better soon :)