Heat oil in a saucepan and add mustard seeds.

The seasoning for the dish is ready, you can switch off the stove for now and keep the pan away from heat so the seasoning will cool down.

Meanwhile mix yogurt in a bowl (using a spoon) to avoid any lumps.

Add salt and water to the yogurt and mix well until well combined.

Once the seasoning is cooled enough (so that the yogurt won't curdle anymore), add the diluted yogurt to the seasoning and mix well.

Add the spices - turmeric powder and red chili powder and mix everything well.

Switch on the stove and heat the saucepan (with the yogurt in seasoning and spices). Stir continuously and watch closely so you can see that the dish is getting slightly hot and the spices are getting blended with the yogurt it starts turning light yellow in color.

Once the dish is slightly hot and starts turning slightly yellow, switch off the stove and keep the saucepan away from heat.  It is very important that you should not bring the mixture to a boil, or it will curdle. Stop cooking and keep away from heat as soon as the dish is slightly hot. Once you have kept the pan away from the stove for cooling, within a few minutes of time, you can see that the yogurt is turned yellow as the turmeric and chili powder has  blended very well with the yogurt.

After few minutes stir gently, and now the moru curry without coconut or yogurt in spices is ready to be served! Serve the moru curry with rice and other side dishes or pickles or chutneys for lunch or dinner!