The answer is very simple: plants! All plants have some protein--even a white potato or an apple. But more specifically, the main vegan protein sources are beans, lentils, nuts, seeds, certain ancient grains, edamame, tofu, tempeh, seitan, and dehydrated soy options (such as soy curls or TVP). There are also fortified options popping up all the time including protein powders, nutritional yeast, non-dairy milks, and more.