There are a lot of other plant based foods with protein besides soy even though soy is a great source used in moderation. 1 cup of black beans have 30% RDA of protein. 1 cup of lentils have closer to 35%. 1 cup of rolled oats about 12%. 1 cup of spinach around 12%. 1/4 cup of peanuts has around 15%. This is just a small sample.