Begin by preheating your oven to 375°F (190°C), ensuring it’s fully heated before baking.
In a large mixing bowl, combine the halved cherry tomatoes, mozzarella balls, and roughly torn basil leaves. Add the minced garlic, balsamic vinegar, and extra virgin olive oil to the mixture. If you enjoy a little kick, include the red pepper flakes. Season generously with salt and freshly ground pepper. Gently toss the ingredients until everything is well incorporated.
Prepare a baking sheet by lining it with parchment paper for easy cleanup. Place the portobello mushrooms, gill side facing up, on the sheet.
Using a spoon, generously fill each portobello cap with the prepared Caprese mixture, pressing down slightly to ensure they are well packed.
For an extra burst of flavor, evenly sprinkle the grated Parmesan cheese over the stuffed mushrooms, creating a delicious crust as they bake.
Transfer the baking sheet to the preheated oven and bake for 20-25 minutes. The mushrooms should become tender, and the cheese will melt into a bubbly, golden topping.
Upon completion, carefully remove the mushrooms from the oven and allow them to cool for a few minutes before serving to avoid burns.
Notes
Serve on a bed of fresh arugula and drizzle with balsamic glaze for an elegant touch.