I tried this to go along with a grilled chicken dish as part of a low-carb meal. Cooked it in the oven at 400 as specified. It was excellent; flavorful and interesting with the garlic and onion pieces getting browned and the asparagus and peppers getting slightly charred in places. Very easy recipe, too. I might cook it a little less than 20 minutes next time, as the asparagus was pretty soft, but my husband approved. :-) This would make a nice company dish. Thanks!