I am a major appreciator of root vegetables. For this recipe I used parsnips, rutabagas, red beets, sweet potatoes and turnips. I really like Gruyere, one of the reasons I chose this recipe, but I think its flavor overwhelmed the vegetables. I made the cheese sauce a bit too thick so it made its own layer on top of the vegetables rather than mixing in, sort of like it's meant to do in pastitsio. I refrigerated the leftovers then peeled off the cheese and topping layer and reheated the vegetables on their own. Everyone liked it better that way. I think we just enjoy root vegetables too much on their own to appreciate them all tarted up.