In a skillet (preferably cast iron), melt your fat over medium-high heat.
While the skillet is heating up, coat both sides of your chicken with the salt, pepper, and cinnamon.
When the skillet is hot, place the chicken in the skillet and don't move it, you want to form a nice crust. If you have one, place a splatter guard over the skillet to keep the grease from making a mess.
When the chicken is cooked about halfway through (time will vary depending on the size of your chicken thighs), turn them over and again, don't move them so it forms a crunchy crust.
The chicken is done when it has an internal temp of 160F. Remove from heat and do not cut into the chicken until it has rested at least 5 minutes. This will make sure it stays nice and juicy.
Serve with roasted veggies (recipe on this site).