Vegetarian with a BF who cannot be filled at meals

I am a vegetarian and do not prepare meat in my house, though I have no problem with people or loved ones consuming meat around me. My BF is around a lot, and I generally end up cooking for him most days. He is a very large man, not fat, but easily 230 and not dieting. I am at a total loss what to feed him. I prepare food for him and myself. I make my normal portion size, usually a 500 calorie meal and then I just triple his portion for him of the same foods. Yet the man is still hungry! He even gets 2nd meals!
I just about threw my hands up and gave up today, when I saw his huge order of take out. 3 cheese burgers, french fries, milk shake and chicken nuggets. This was a large meal that day, but there is just no way I am ever going to be able to compete or feed someone that amount of calories on a vegetarian diet
For example I am going through 2 cartons of eggs a week feeding him breakfasts of 4 eggs with beans and veggies to bulk up the meals.
-frustrated and at a loss here