I got this recipe from a fellow blogger, and changed a few things due to lack of ingredients on hand. I used parsnips instead of sweet potatoes, and collards in place of half the chard. And I didn't have gruyere, so I used fontina. Substitution is my middle name. Here is a link to the original recipe. I didn't use quite as much bechamel as she uses, because I wanted to be sure I could cut it into squares easily. It was delicious and very time consuming. I served it with braised seitan in red wine sauce.