I had duck breast in a restraunt once, but that wasn't muscovy and I didn't care for it. Muscovy is all dark meat. So I stuffed the cavity with quartered apples and onions like I would for chicken or turkey. (That's my secret for keeping poultry moist.) Then I made a glaze with orange juice, brown sugar, ground ginger, garlic powder and salt and pepper. I poured the glaze over the top of the duck, which was sitting nicely in a roasting pan, and put it in the oven set at 400 degrees. Then waited and waited and waited some more. The duck took longer than expected to cook, about 2 1/2 hours total. Maybe closer to 3, I don't remember exactly now.
When it came out of the oven, it looked like this:
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And it tasted as good as it looked. The flavor is hard to describe, but it was amazing. Imagine crossing a cow and a chicken. Then you'd be close. And the texture was very similar to beef as well. If you ever have the chance to try it, I would highly recommend it.