In a large bowl, mix yeast with ½ cup warm water and stir to combine.

Add teff flour, rice flour and salt.

Gradually add more warm water, stirring with a wooden spoon until you have a smooth batter, it should be the consistency of thick pancake batter. You may not need all the water.

Cover with plastic wrap and let stand for 1 hour at room temperature.

After an hour, the batter will thicken a bit, stir and pour in the hot water, stirring constantly until you get a thick crepe batter.

Let stand for 20 minutes, then proceed to cook.

Ethiopians cook injera on a non stick electric griddle. If you have that, use it, if not, a large non stick flat griddle or frying pan will do. Heat the pan over medium-high heat.

Transfer injera batter to a jug. When the pan has heated up, starting from the outside of the pan, pour your batter from a height of about 6 inches, in a circular motion, completely covering the pan.

If you need to tilt the pan to cover all of it, do it quickly, as the batter will crisp up fast. But it's better not to tilt the pan. It may take you a couple of attempts to get the hang of it.

At about 30 seconds, you'll start to see air pockets or holes on the surface. Cover the pan with a lid and cook for 1-2 minutes until the edge is curling up. If your batter was on the thinner side, it takes one minute to cook. So time the cooking for 1 or 2 minutes (or even 3) depending on the thickness of the batter.

Remove to a plate or basket and cover with a towel to keep from drying out. Injera should stay fresh for a couple of days.