Trim your duck breast of excess fat.
Score breast in diagonal pattern approx 1/2" wide.
Pat dry skin.
Dust duck breast with chinese 5 spice.
Set up BBQ for indirect heat to 400°F.
Smoke duck breast using pecan or cherry until internal temp of 150°F, approx 20-30 mins.
Rest duck for 2 mins.
Place cast-iron skillet onto direct heat with a drizzle of oil.
Cook duck breasts skin side down for 1-2 mins to render fat and crisp skin.
Remove from the pan and cover with foil.
Wipe out the skillet and return to heat.
Pour in cherries with half the syrup, port, marmalade and all sauce ingredients.
Reduce until thick and syrupy.
Slice the duck breast thickly.
Serve the duck with sauce, greens and mash.