Measure and add all dry ingredients to a large bowl.
With a whisk, blend all the dry ingredients together thoroughly.
On the stove, heat a large cast iron pan on low to medium heat and add roughly 1/2 cup to 1 cup of pork lard (or cooking oil of choice).
Slowly pour in the club soda starting with 1 1/4 cup. If your batter is too dry, add up to 1/4 cup more as you stir.
You will want your batter to be just as thick as pancake batter, but not as thin as cake batter.
Dip each chicken thigh in the batter, making sure to coat each side with a thick layer.
Immediately put your battered chicken thigh into your cast iron pan. You will generally be able to fit 3 battered chicken thighs in your pan at a time.
After about 5 to 7 minutes, or when the chicken thigh starts getting brown and crispy on the bottom, carefully flip it over using a metal flipper. Be careful not to spray yourself with the hot lard! I suggest wearing oven mitts and an apron. Cook for another 5 to 7 minutes.
Once your battered chicken thighs are done, carefully scoop them out with a flipper and place them on a plate lined with paper towel. This will soak up some of the extra grease. Cut into the thickest chicken thigh to make sure that the chicken is cooked through. If it's not, drain out some of the grease and put them back in the pan at a lower temperature to allow them to cook through more thoroughly.
Serve as soon as possible! They will be nice and crisp when they first come out of the pan, but quickly lose their crispy texture. Serve with a mixture of 1 tablespoon honey, 1 tablespoon yellow mustard, and 2 tablespoons of mayonnaise. Trust me!
Above in the blog post I provide recipe ingredient substitutions as well as recipe variations.