If you want a complete protein in one food, tofu is probably your best bet. However, since you're probably not going to want to eat that every day, the best thing to do is eat a variety of high protein foods. Mix your proteins in order to get complete proteins. So, have say a grain (quinoa, millet, or brain rice are good) and have it with beans, or tempeh, or seitan, or nuts, etc. If you search for specific foods on that site, it'll show you which of the amino acids that food contains, and let you search for foods with complementary proteins. So if you want to be extra sure you're getting enough complete proteins, check what you're eating to see the amino acids in all of the different foods.