Using the tip of a boning knife, slice along the top of the thigh bone, slowly exposing the bone on either side but not cutting too deeply into the meat.

Gently separate the bone from the meat and reserve the bones for making chicken stock.

Place a large skillet in the oven and preheat the oven to 450F.

Place the salt, white pepper, black pepper, mustard, garlic powder, paprika, rosemary, thyme, and marjoram in a small bowl, blender, or mortar.

Using the back of a spoon, blender, or a pestle, grind the spices to powder.

Place the deboned thighs skin side down in a large bowl and sprinkle the spice mixture over the thighs.

Using tongs or your hands (wash your hands well before and after), turn the thighs several times to coat the thighs with the spices.

Place the thighs skin side down in the skillet and return the pan to the oven.

After 5 minutes, remove the pan from the oven, drain any fat from the pan, and using a spatula or tongs, press the thighs into the skillet to make sure the skin comes into full contact with the pan. Return the pan to the oven.

After another 5 minutes, repeat the draining of the fat and pressing of the thighs and return the pan to the oven.

After 2 minutes turn the thighs to skin side up and replace the pan in the oven.

Turn the heat to broil and broil for up to 5 minutes or until the skin is browned and crispy around the edges.

Do not overcook.

To serve, place each cooked chicken thigh on a bun and top with lettuce and tomato. Serve immediately.