Portobello Pita Pockets

I've only made this once before, but it was really good. My husband is watching his cholesterol, so I figured portobello mushrooms would be a good substitute for hamburgers because of their meaty flavor. He really liked them. I'm not sure what we'll have on the side. I bought some corn on the cob yesterday, so I may grill that up while I'm doing the mushrooms and onions.

Portobello Pita Pockets
3 Tbsp balsamic vinegar
1 tsp olive oil
1 tsp dried rosemary
3 garlic cloves, pressed
1/4 tsp salt
1/8 tsp ground black pepper
1 medium onion, sliced into 1/2-inch thick slices
4 medium portobello mushroom caps (3-4 inches in diameter)
2 whole wheat pita pocket bread rounds, cut in half
2 plum tomatoes, sliced
1 cup packed fresh baby spinach leaves
4 slices reduced-fat Swiss cheese

Combine vinegar, oil, rosemary, garlic, salt, and pepper. Set aside 2 tablespoons of the vinegar mixture. Brush both sides of the onion slices and mushroom caps with remaining vinegar mixture.

Heat grill (or grill pan) to medium high heat. Place pita bread rounds on grill, grilling 1-2 minutes on each side. Remove from grill. Place onions and mushrooms on grill; cook 4-6 minutes or until vegetables are tender and have grill marks, turning once.

To assemble sandwiches, cut pita rounds in half. Line each pita round with spinach leaves, one slice cheese, one slice onion, one mushroom cap, and tomato slices. Drizzle each pita with reserved vinegar mixture. Serve immediately.

Now, when I made it last time I found an entire slice of onion was way too much onion for my liking, so I just put a couple rings into each pita. I also didn't like drizzling the extra vinegar on the sandwiches as I thought that made it too soggy. We're using Provolone cheese instead of Swiss tonight, too.