What are some techniques to cool down a dish so that we can store it in the refrigerator safely?
There are several things in general that you can do to increase the speed at which food cools down, but two of the most effective are:


Increase the surface area.  Spread it in a wide, shallow pan, like a sheet pan, rather than a deep pot.  This will allow more cooling.
Use an ice water bath.  Place the container with the food into an ice water bath, being careful not to spill the water into the food.  Using a zip style bag to hold the food before putting it into the bath also can help.

A variation of this, especially for hot stocks or stews, is to freeze water in clean water bottles or zip bags, and place those into the food in addition to the ice bath.


For a pilaf, the first method should work very well.

You can also bring physics to the party:


Convection is far more powerful at heat transfer than conduction.  A fan for air cooling will help, or running water for water for water cooling will also help, but these are not always practical in kitchen.