1. Start by cleaning the portobello mushrooms, carefully cut the stems off, clean the top of the Mushroom with a damp clean towel, and use a spoon to scoop out the gills (this is optional because leaving the gills in adds an earthy flavor to your meal).
2. Then make the marinade in a bowl, plastic zipper bag, or glass baking dish. Mix the balsamic vinegar, soy sauce, thyme, ginger, rosemary, garlic, and olive oil. Mix thoroughly and add the portobello mushrooms covering every side of the Mushroom with the mixture using a spoon and your hands; if you’re using a plastic bag, seal it and shake the mixture, so it mixes thoroughly.
3. Let it sit for a few minutes, about 15-20 minutes.
4. Preheat the oven to 400°F and bake the Mushrooms for about 15 minutes with the stem side facing up. (This is optional, and you can bake however you like, this is just how I like doing it).
5. After 15 minutes, flip it over with a spatula and bake for another 15 minutes with the stem side facing down.
6. When the times up, remove the portobello mushrooms, slice them to the desired shape and serve warm with any dish or topping; you could serve with salad, rice, or even chop and add some nice-looking veggies on top of the sliced Mushrooms.
7. If there are any leftovers (which I doubt there would be), you could store them in a refrigerator for 2-3 days.

This recipe is really easy and delicious to make but if you’d like more ideas or need some inspiration for your portobello mushroom recipe, check out this video recipe.