Quinoa and Aramanth are grains that are high in protien and do have all the essential amino acids humans need. I haven't tried Aramanth yet, but Quinoa is delicious and extremely versatile.

Nuts are great, but if you have a tendency to overeat them, it's probably better to not snack on them exclusively (meaning that your whole snack is just nuts). Use them to supplement other foods (like on a salad or as a topping) so that they aren't your sole source of calories at that particular meal/feeding. I find this makes it easier to include them in the plan without the danger of over-eating them (an issue for me).

Ricotta, cottage cheese, yogurt, milk and many types of cheeses are great ways to increase your protien, too. While dairy is not an essential part of the diet, it is an easy way to add variety.