Melt the butter in a large saute pan over medium-high heat. Add lamb, season with salt and pepper, break into tiny bits, and cook until brown and crispy. This takes about 8 minutes. Drain off excess fat.
Stir in the uncooked rice and cook for a few minutes until the rice turns translucent.
Pour the bone broth into the pan and bring it to a simmer. Stir and cover pan over low heat until the liquid is absorbed and the rice is fully cooked, about 15-20 minutes. 
Turn off the heat and let the mixture sit for 5 to 10 minutes.
Then scoop out of the pan onto a platter, top with yogurt, pistachios, fresh mint, and cucumbers.