Heat the water slightly. Dissolve the yeast and sugar in 2/5 cup (100 ml) of it. Cover the container and leave it to activate for 10-15 min. In a deep bowl, beat the eggs with the salt, add the yoghurt and remaining cool water.
Sift the flour and begin to add it in lots.
Add the activated yeast. I used dry yeast (1 1/3 tsp (7 g)). You don't need to activate it ahead of time. Add it to the flour and stir with the rest of the products.
Cover the container with a towel and leave to rise in a warm area for 30-40 min. Once bubbles form on the surface, the mixture for the crepes is ready.
Heat a Teflon pan, smear it with oil, scoop a ladle of the mixture and pour into the center of the pan. Spread it out with swirly movements. Cook on one side, then flip over with a spatula.
The stove must not be too high (I cooked on 4 out of 6) because you have to cook the crepes a bit slower, so they remain raw in the middle. After each crepe, smear the pan with a few drops of oil.
Smear each ready crepe with softened butter. This mixture was enough for 10 crepes. Serve with feta cheese or jam of choice.