Make the marinade. To do this, combine 1/4 cup olive oil, along with the garlic, red wine, soy sauce and freshly ground black pepper in a medium bowl. Stir to combine.
Now add the mushrooms to the marinade. Toss them a couple times to make sure they all get nicely coated, and let them hang out there for about a half hour.
Strain the mushrooms, reserving the excess marinade for later.
Start making your polenta. To do this, bring 6 cups of water and 1 tsp salt to a boil in a large pot over high heat before slowly stirring in the polenta. Once you've added the polenta, reduce the temperature to a simmer and cook it for about 30 minutes, or until it's nice and thick. You'll want to stir frequently to prevent sticking and/or burning.
While you wait for your polenta water to boil, heat 1 tbsp olive oil over medium high heat in a large pan. Then add the mushrooms and a sprig of rosemary and cook for about 10 minutes, or until most of the liquid that the mushrooms released is gone.
Add the remaining marinade to the pan and reduce the heat to medium. Cook for another 15-20 minutes (stirring every so often), or until the sauce had reduced and thickened to your liking. Add a little salt to taste if you'd like (though this should be plenty salty because of all the soy sauce).
By this point, your polenta is probably quite thick. Stir in the butter and goat cheese, along with a bit more salt if you feel that it needs it and remove from heat.
Divide the polenta into 4 bowls, making an indentation in the middle for mushrooms and sauce. Then add even portions of the mushrooms to those indentations. Top with a bit of goat cheese and a little rosemary if you'd like, then enjoy!