Portobello Mushroom Burger
Per 1⁄2 English muffin
1 English muffin, cut in half
2 teaspoons butter
1 large portobello mushroom
1 romaine lettuce leaf
1 teaspoon olive oil
3 tablespoons (or to taste) chopped onion
1 tomato slice
2 tablespoons grated Swiss cheese
Toast the English muffin halves. Spread 1 teaspoon butter on both halves while still warm, and set aside. Wipe the portobello mushroom with a damp cloth and cut into thin slices. Wash the lettuce leaf, dry, and tear into pieces.
Heat the olive oil on medium in a skillet. Add the chopped onion and cook on medium-low heat until tender.
Add the remaining 1 teaspoon butter to the frying pan. Push the onion to the side and lay the portobello mushroom slices flat in the pan. Cook until browned on the bottom, about 2 minutes. Turn over and cook the other side until browned. Add the tomato slice to the pan while the mushroom is cooking for the last 2 minutes.
When the mushroom slices are browned on both sides, sprinkle the grated cheese on top. Cook briefly until the cheese is melted.
To make the burger, lay the tomato on 1 muffin half and place the cooked onion on the other half. Lay the mushroom and melted cheese mixture on top of both halves. Serve open-faced, garnished with the lettuce.