This is the recipe for injera made from t'ef flour offered by Exotic 
Ethiopian Cooking (that cookbook). I have never tried it. 
Someone asked me for it, so I typed it up.  

Injera made from flour works quite well, and it's much easier
to use, so I recommend it.

1 1/2 lbs t'ef flour
6 cups water
2 pkt yeast.

Sift t'ef into a deep mixing bowl. Add water gradually and working with 
your fingers to avoid lumps. Work into a dough.

In another pot dissolve yeast in some warm water. Add to the flour. Mix. 
Leave the dough uncover until fermentation starts (the water will rise to 
the top), 2 or 3 days. Discard the water.

Separately boil 2 cups of water. Add 1 cup of the dough to the boiling 
water. Put on the stove (make sure it's warm), and stir continuosly. When 
it becomes thick, remove, and cool down. Return to the original pot. Add 
more water, cover and let stand until it rises.

Now you are ready to finally cook the thing :)

Preheat a pan to about 420 degrees (use a non-stick pan or a pancake 
pan).  Pour about 3/4 cups of the mixture into the pan, starting at the 
edge and going in circles towards the center. Cover and cook for 2-4 
minutes. The rim of the injera will rise when it's done. Remove immediately