I modified this vegetarian stuffed zucchini recipe  from Suite101.com to turn it a main dish and to incorporate some fresh organic mushrooms. I also used panko instead of bread crumbs.
Megabeth’s Vegetarian Stuffed Zucchini Recipe
- 1 zucchini and 1 yellow squash (wash and use a vegetable brush to remove any remaining dirt.)
- 2 tsp. olive oil
- 2 cloves garlic, minced
- 1 tbsp. minced green onions (I used white parts only)
- ½ – 1 tsp. dried oregano, to taste
- ½ – 1 tsp. dried basil, to taste
- Salt and pepper, to taste
- 1 cup pasta sauce (I used a tomato basil sauce)
- 3 tbsp. panko crumbs
- 2 tsp. Parmesan cheese or nutritional yeast
- 7 or 8 large white mushrooms, diced into small pieces
Directions (I have reprinted the directions from the original recipe  as the steps remain the same. My additions and comments are in italics.)
Bring a large pot of salted water to the boil. Cut off the knobby ends of the washed zucchini and trim off any remaining blemishes on the skin with a knife.
When water on stove is boiling, carefully place zucchini in with tongs. Boil for 10 minutes, or until a fork easily pierces the zucchini.
Meanwhile, preheat the oven to 350ºF (180ºC). Using tongs, carefully remove zucchini from water and let sit until cool enough to handle.
While zucchini is cooling, heat olive oil in a medium skillet over medium-high heat. Add onion and garlic and stir well to avoid burning. Sauté for 2-3 minutes. Add diced mushrooms and saute until soft.
Add tomato or spaghetti sauce and heat through. Stir in breadcrumbs (or panko), oregano, basil, salt and pepper to taste.
Cut cooled zucchini in half, lengthwise. Using a spoon, scoop out the insides (seeds and flesh) and save in a small bowl. Chop any pieces that are larger than bite-sized.
Add zucchini pulp to sauce mixture.
Fill the empty zucchini shells with the sauce mixture and top each with parmesan cheese or nutritional yeast, if desired.
Bake on a baking sheet or stone for 15 minutes or until cheese is browned. Serve with a knife and fork.