Balsamic and Thyme Marinated Portobello Mushrooms

Balsamic and Thyme Marinated Portobello Mushrooms

Easily one of the best things about the whole30 is that it’s stimulating my creativity. I typically have my go-to vegetables that I love. Those always include Brussels sprouts, butternut squash, and leafy greens. John will always happily eat all of the vegetables that I prepare…as long as they’re accompanied by some type of pasta. There’s something in his Italian heart that makes him undeniably and inexplicably in love with pasta. So yeah, those vegetables are fine, but they are preferably little bits swimming in a sea of pasta (and butter. Lots of butter).

I’ve been trying to make different dishes that will be mentally satisfying. John is the type of person that will say that he didn’t really have lunch if he happens to have a Cobb salad, because “it’s just lettuce.” But let’s just ignore the fact that there’s 4 ounces of chicken, 2 strips of bacon, half an avocado, a whole egg, and dressing. But yeah, pretty much just vegetables.


For that satiation factor I looked to portobello mushrooms. I can use a whole host of words that quickly sound unappealing to describe them, but they really are big and beefy. (I hesitated in even going there, because it sounds like I’m talking about a ‘roided bodybuilder in the mid 80s, but alas.)

But look at them, really. There is no way this won’t be satisfying cutting into this. And if you happen to be one of those people who like the texture of mushrooms (John and me!), then you’ll love these. I think roasting the entire mushroom also just seems more satisfying than small pieces of mushrooms of equal weights.

So then let’s talk about how we really elevate their flavor. They’re flavorful enough, but they’re even more flavorful when marinated for 15-20 minutes prior to baking. I simply used about a 1:1 ratio of balsamic and olive oil. Use good quality balsamic and olive oil, because with something with such few ingredients, you don’t want to sacrifice any flavor. I added some garlic and thyme, both of which go well with the mushrooms. Thyme is my second favorite herb (Sage is number one in my heart per the previous post LINK TO SOUP). I use it all of the time and always happen to have it on hand to make something like this (LNK TO BURGERS).

The flavors of the thyme, garlic, balsamic and olive oil have a chance to meld as they hang out for 15 minutes. Then they’ll roast in the oven for anywhere between 15-25 minutes, depending on the thickness of the portobello. This is an exact science and is much more forgiving than, say, something like steak. OH! But salt them after roasting. If you salt them before, then the salt will draw out the moisture of the mushroom during baking, which will affect the overall texture. Also, be creative: use whatever flavored balsamic, herb, seasoning that you’d like. It’s quick and easy and will be on your plate before you know it.


Balsamic and Thyme Marinated Portobello Mushrooms


2 large portobello mushrooms, ends of stems trimmed

1-2 tablespoons good quality olive oil (not extra virgin)

2 tablespoons good quality balsamic

2 teaspoons fresh thyme

2-3 teaspoons minced garlic

Salt and pepper


Preheat the oven to 425 degrees. Coat the bottom of a 2-3 quart dish with olive oil.

Clean the mushrooms by using a damp paper towel or cloth and removing any dirt. Be careful not to bruise the pretty mushrooms. Place in the baking dish.

Drizzle olive oil and balsamic evenly between the two mushrooms. Sprinkle with thyme and garlic. Let sit for 15-20 minutes. (I have even done a half hour)

Roast for 15-25 minutes, depending on the thickness. They should be supple yet somewhat firm when you cut into the center. Season with salt and pepper to your liking.

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