Hubby hates Brussel sprouts so I used broccoli instead. I also used shallots instead of a red onion & added celery & fresh mushrooms. For the sauce, I added fresh garlic & brown mustard. It took closer to 40 minutes before it was done. When finished, I garnished with parsley & fresh cranberries. So good- hubby loved it! Next time I'll add some parmesan cheese.
One important note for those new to cooking: it is VERY important to avoid cross contamination when adding the sauce. Pour some sauce on the chicken first, THEN spread with a brush if desired. This will keep the remainder of the sauce clean until it is ready to add later.