3/4 pound sliced mixed mushrooms, such as cremini, shiitake and button
1/2 teaspoon kosher salt
1/4 teaspoon freshly ground black pepper
1/4 cup oil-packed sun-dried tomatoes, drained
1 cup (4 ounces) shredded fontina cheese
Directions
Mince the shallots and the thyme leaves. Cut the polenta crosswise in half, then cut each half into quarters, then cut each of those quarters in half, making 16 equal slices total. Set aside.
Melt 1 tablespoon of the butter in a medium skillet over medium heat. Add the shallots and cook for 3 minutes, stirring, until they have softened. Add the sliced mushrooms, thyme, salt and pepper.
Cook for 5 minutes, stirring, or until the mushrooms are tender and have exuded liquid.
Reduce the heat to the lowest possible setting
Keep warm.
Meanwhile, finely chop the sun-dried tomatoes and combine with the shredded fontina cheese.
Heat the remaining tablespoon of butter on a large nonstick griddle over medium heat until the butter is bubbly. Arrange 8 polenta slices on the griddle and sprinkle them with the tomato-cheese mixture, using most of it. Top with the remaining 8 polenta slices to form sandwiches.
Cook for 3 minutes, then carefully turn over the sandwiches and cook for 3 minutes or until the cheese has melted and the polenta has deepened in color. (For an optional panini effect, place a second pan or heavy pot on the sandwiches to press them.)
Turn off the heat
Sprinkle the remaining tomato-cheese mixture on top of the 8 sandwiches so that it melts slightly and let sit for 1 minute
Rransfer to individual plates (2 sandwiches per serving) and top with the mushroom mixture.