Preparation 15 minutes, rest 2 days, baking 10-15 minutes.
Allow the citrus peels and lavender flowers to dry for one or two days. Place them on a sheet of paper towels and place the latter on a radiator. If there is no time, pass them through the oven being careful not to burn them.
Lightly toast the cumin and coriander seeds in a frying pan without adding fat.
Reduce the citrus peels, seeds and flowers to a coarse powder.
Brush the meaty side of the duck breast with olive oil, sprinkle the spice mixture over the duck breast, season with salt and pepper, and finally bake in the oven for 10-15 minutes at a moderate temperature, skin side down.