Remove stems from mushrooms and chop finely. I'm not a chopped so at this time I pull out the electric processor. If you are using the bell peppers, you should only use 1/4 cup of the mushroom stems. I use all of them. Combine the onion through the garlic.
Heat a skillet over medium, coat the pan with cooking spray. Add the chopped veggie mix to the pan and cook 10 minutes until they are tender.
Toss the veggie mix and the bread in a separate bowl. Add the broth slowly, tossing to coat. Add feta and toss gently.
Coat a baking sheet with cooking spray.
Brush cleaned mushrooms with 1 tablespoon of the vinaigrette, sprinkle with parmesan and black pepper, top each mushroom with 1/2 cup of bread mixture.
Bake for 25 minutes or until mushrooms are tender.
Combine remaining 2 tablespoons of dressing and salad greens.