Loaded Sweet Potato Sandwich

A friend of mine, who does an excellent job at eating lots of produce, has a child with dairy allergies. Despite this, the child loves cheese and grilled cheese sandwiches. Trying to come up with an alternative, my friend came up with this version of a grilled "cheese" sandwich. The bread is still grilled, but the filling is totally healthy and totally delicious (and for the benefit of her son, totally dairy free)! When she shared the recipe with me I had to try it, and my expectations