Heat oil in a pan over medium heat.
Once the oil is hot, add peanuts and cashew nuts (halved) and fry until they are lightly browned, stirring frequently.
Push the fried peanuts and cashew nuts to the side of the pan.
Add curry leaves and fry until crisp, stirring continuously. Once done, mix everything together.
Reduce the heat to low. Add asafetida, white salt, black salt, turmeric powder, and red chili powder, and saute for 5-6 seconds.
Now add puffed rice to the pan and mix well to coat with the spices.
Fry on low flame for 7-8 minutes or until the murmura is crispy and crunchy, stirring very frequently. Finally, add dry mango powder and powdered sugar and mix well.
Remove the pan from the heat and let the namkeen cool completely. Transfer the cooled namkeen to an airtight container and store it at room temperature for 2-3 weeks. Serve!