I am not a vegetarian, but this is one meatless sandwich that satisfies my carnivorous cravings.
2 slices bread (whole-wheat preferably)
1 giant portobello cap, stemmed and sliced
a handful of spinach
a slice of cheese (Jarlsberg works well with this)
1-2 tsp. oil (canola, olive, or Enova)
1 tsp. balsamic vinaigarette
Saute sliced mushroom in skillet for 2 minutes, add spinach and continue saute until spinach's wilted. Spatula them into a square and top with slice of Jarlsberg cheese. cover skillet for 30sec-1 minute. spread balsamic vinaigarette over bread slices the spoon the mushroom-spinach-cheese mixture onto bread and enjoy!
My estimate for calories is 400-500 (primarily in bread, the balsamic vinaigarette, cheese, and oil) but it's oh-so-delish and filling!