Half cook the chicken over low heat in some water with the onion. Take off the white foams that will come out. Keep cleaning the foams until no more foams come out then change the water (by doing so you'll take out that bad taste that could appear in boiled chicken) now that you've changed the water cook the chickens in low heat until it is cooked well.

Mix the 4 cups of yogurt with the two cups of water.

Solve the starch in 1 cup of cold water then add it to the mixture that you've already prepared.

Cook the mixture in a pot (you're going to have to keep stirring the mixture until it starts boiling otherwise the yogurt and the water are going to be divided) when the mixture is boiling add the chicken and cook everything for 10 more minutes.

Add the crushed garlic and coriander at the very last 5 minutes of cooking (that is going to save their flavor)

Preparing the Rice: Wash the rice and keep them in water for 10 minutes.

Melt the butter in a pot and fry the vermicelli with some salt. Then add the rice and fry it for 30 to 60 seconds then add the 3 cups of hot water) let the rice cook over low heat for about 15-20 minutes. (let it steam so the pot should be closed well)

You can also cook the rice simply in a rice cooker.