1. Use a standard, sharp kitchen knife to slice through the joint where the thigh and drumstick meet. The cartilage at this joint is extremely soft, so your knife should feel little resistance.
2. The leg has now been split into thigh and drumstick pieces. The drumstick can be boned using the exact same method as boning the thigh.
3. Make an incision along the top of the bone. Deepen the incision by slicing into the thigh until your knife reaches bone. The bone will be visible through the incision: it will be white and very firm.
4. Grasp the now partially disconnected bone and pull it up and away from the thigh so you can slice underneath the remaining bone. You will feel the bone begin to loosen from the thigh. Make the necessary cuts to remove the bone completely from the thigh.
5. Slice the meat away from the bone by making several short cuts with your knife. As the meat comes free, use your fingers to pull it clear of the bone.
6. Continue slicing until you have removed any unwanted bits of bone, sinew, tendons, and skin (if desired). The thigh is now ready to be used in your favorite chicken recipes.