Nuts and legumes! I love adding beans or lentils to my salads Try finding more caloric dense foods that you enjoy eating and add them to your diet.
Eating healthy is a big step, congrats on making that decision! Good luck with your recovery

Have fun with salads. Try different food combinations. Dark greens with strawberries, walnuts, other nuts, chopped zucchini, tomato, peppers, radishes, onions, blue berries, quinoa, beans, just about anything. Try different dressings that you can make yourself.

My other half is trying to gain weight atm and is scoffing cans of coconut milk in things (like drinks and curries). It may help

Coconut milk is horrid. Leave it out. Just eat more beans and lentils, more fruit and vegies, more nuts and seeds. Olive oil. Pay attention to your nutrition if you are not eat meat or dairy. I've just started with mostly vegan eating. And i've noticed that bean and lentils recipes are very very good for filling you up. I also have recently started making my own pasta. Pasta is not that bad. Its high in protein if you are not eating meat. But eat everything with lots of vegetables. No need to be shy with the olive oil. I use peanut oil for frying. I will have to take a b12 supplement and probably some calcium as i think its going to be too difficult for me to get enough calcium from my food even though its good. I prefer not to eat processed foods. They are more expensive and less healthy but i am making the concession of drinking some soy milk. I eat tofu but you can't eat that all the time. I don't like tempeh or other pretend meat replacements. I make all sorts of lentil and bean patties.

You can follow my blog if you want to see how I make food. There's a link on my profile page. I have only jsut started but i have been eating whole foods for a long time now.

I do share the same struggle of recovering /still struggling with an eating disorder, mine is different however the nutritional need is the same and I went vegan almost a year ago now and filling up on various salads with beans, avocado, nuts, and different dressings is a quick easy way to get the nutrition and extra calories and healthy fats. Good luck and stay well!