• Heat one chimney full of charcoal.
• Score the skin side of the duck breasts in a cross-hatch pattern with a sharp knife. Try to not score into the meat at all. 

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• Season the breasts with salt and pepper, rubbing the seasonings into the scoring. 

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• When the coals are heated, pour all of them except a few into your grill in one single, rather thin layer. Add more coals onto the ones remaining in the chimney to fill it halfway again. (Now you have almost one chimney full in the grill and half a chimney heating back up.)
• Place the cast iron pan on the grate above the coals. 
• Place the duck breasts, skin-side down, in the pan.

• As they start to render, check the heat. You want enough heat in the pan so that the fat gently bubbles, but not so much that it’s spattering or acting angry. If your pan is too hot, spread the coals out a little bit more. 
• Place the lid on the grill and cook, checking every few minutes. 
• When a lot of fat has accumulated in the pan, pour it off into a heat-proof container for later use. Continue to cook. The rendering process should take 10-15 minutes. 
• When the skin on the breasts is well rendered and a beautiful, chestnut brown, it’s time to sear. The internal temperature should be in the range of about 100°F (38°C).

• Remove the pan from the grill and add the half-chimney of coals to your coal pile. 
• Place the duck breasts, without the pan, on the grill grate above the coals and cook, skin-side up.

• Take the temperature every couple of minutes. Use your Thermapen ONE to look for a lowest temperature of 130°F (54°C). 

• When the pull temperature has been reached, remove the duck and allow to rest for a few minutes before slicing and serving.