Add balsamic vinegar to a small saucepan on medium heat. Bring to a simmer and add the brown sugar. Stir until you no longer feel the crystals of the sugar. simmer stirring often for about 8 minutes until the glaze reduces by half. When you run a spoon through the pan, the glaze should lazily come back together.
Mushrooms
Preheat the oven to 425℉. Bring a large saucepan to medium-high heat. Add your ground sausage to the pan. Let it sit for 2-3 minutes to develop a crust. Then stir the sausage and repeat. Stir again and make sure the sausage is browned. It doesn't have to be completely cooked through.
Prepare the mushrooms, by removing the stem. Place the hot, cooked sausage into the mushrooms. Top with the parmesan and mozzarella mixture. Place directly in the oven and bake for 10 minutes.
Remove and top with sliced roasted red peppers. Drizzle with balsamic glaze and garnish with basil.
Notes
Balsamic glaze process: One BIG mistake I made when making the glaze is that I poured the balsamic vinegar into the pan while the pan was hot. The sugar particles basically turned to dust! Start with the vinegar in a cold pan and then once it is hot, add the brown sugar.
You can cool the balsamic glaze in the fridge so it will thicken and not leak through the mushroom.
Chop up the mushroom stems and add them to the ground sausage while cooking to avoid any WASTE.