I like the way baby bella mushrooms look in this recipe. The deep coloring with the dark red of the grape tomatoes really makes this a beautiful side dish. But, white button mushrooms look the same when they're cooked, so that's why I use those. Whatever you can find in store (and whatever is cheaper) is the way to go. We don't recommend other mushrooms, like portabella mushroom, in this recipe. We love portabella, but they just don't work in this recipe.