Balsamic Roasted Mushroom and Zucchini French Bread Pizzas

Ingredients (9)

• 12 oz. assorted mushrooms, whole (I used a mix of crimini and shitake
• 1 small zucchini, cut into slices
• 1/2 a large yellow onion, sliced
• 2 Tablespoons olive oil
• 2 Tablespoons balsamic vinegar
• Salt and Pepper
• Bread of choice, sliced down the middle then halved OR just 4 thick slices bread of your choice (I used a Rosemary and Olive Oil)
• 4 Tablespoons butter, melted
• LOTS of shredded cheese (I used Gouda and didn't measure--OOPS!, but I'm, guessing it was about 8-12 oz.)