Use a sharp knife to lightly score the skin side of the duck breast in a criss cross pattern, being careful not to cut too deep (you should not cut through to the meat).

Season the duck breasts with the dry rub and let sit until the smoker is ready.

Place duck breasts skin side up directly on the smoker grill grates.

Insert a meat probe in the thickest part of the breast.

Close the door. Set the dial to Smoker. Set the temperature to 250°F. If you have the Ninja Woodfire Pro, you can use the built-in temperature probe to monitor the meat temperature. Set it to 130°F. The machine will turn off when the meat reaches that temperature.

If you don't have the Pro, you should set the timer for 20 minutes of cook time and about 15 minutes in, check it with an instant read digital meat thermometer.

Select START/STOP to begin cooking.