Teff
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If you've ever eaten the spongy injera flatbread in an Ethiopian restaurant, you've had teff. But the tiny seeds of this grass aren't only good for making injera. "It makes a great hot cereal," Thompson says. Just cook it the same way you'd cook oatmeal (but follow the directions to get the correct amount of water to use). "It's a really good source of iron, fiber and thiamin."