A vegetarian burger made with grilled portobello mushrooms and grilled onions, spinach, and sun-dried tomatoes.
- 4 portobello mushroom caps
- Olive oil
- One 8-ounce jar of sun-dried tomatoes in oil
- 8 ounces of baby spinach
- 1 red onion, sliced into 1/4-inch rounds
- 4 hamburger buns
1 Prepare your grill for high, direct heat.
2 Wilt the baby spinach: While the grill is heating, if you wish, sauté the baby spinach in a tablespoon of olive oil and a sprinkle of salt in a large sauté pan on medium high heat, just until the spinach wilts, then remove to a plate.
The gently wilted spinach will stay on the portobello mushroom burger better than raw spinach, which tends to fall off.
Or you can use raw baby spinach. Your choice.
3 Clean mushrooms and brush with oil: Wipe the mushrooms clean with a damp paper towel. If you are working with whole mushrooms, slice off the stems (you can use for another purpose, chopped and sautéed or for making stock.)
Paint the tops of the mushroom caps with some of the oil from the sun-dried tomatoes.
4 Grill onion rounds, mushroom caps, buns: Scrape the grill grates clean. Using a folded up paper towel dipped in olive oil, wipe down the grill grates to oil them.
Brush the onion rounds with some olive oil and place them on the grill.
Place the mushroom caps on the grill, top side down first. Sprinkle with a little salt. Grill the mushroom caps and the onion rounds for 4-5 minutes per side.
Grill the burger buns, cut side down, for about 1/2 to 1 minute, until lightly toasted.
5 Assemble: To assemble, spread some mayonnaise on each bun. Put a portobello mushroom cap on the bottom, then layer on the spinach, sun-dried tomatoes, and finally some onion. Serve at once.