Preheat oven to 450°F, and coat a baking sheet with olive oil.
In a small mixing bowl, mix together the olive oil, Italian seasoning and garlic.
Spread the mixture on the portobello mushrooms. Add the pizza sauce on top, followed by the mozzarella cheese and then the sliced cherry tomatoes.
Bake for 8-10 minutes in the preheated oven until the mushrooms soften slightly and the cheese melts. Enjoy immediately.
Video
Notes
Storage: Store any leftovers in an airtight container in the fridge for up to 3 days, although it's best to enjoy these immediately after baking. Reheat in the oven at 350°F for 5 minutes until warmed through.