4 sandwiches

4 large Portobello mushrooms, stems removed
1½ tsp. Dijon mustard
2 cloves garlic, chopped
2 tsp. thyme, fresh
2½ Tbs. balsamic vinegar
2½ Tbs. extra virgin olive oil
Kosher salt and freshly ground black pepper to taste
¼ cup all-purpose flour
1 each egg, beaten
½ cup Panko breadcrumbs
8 slices country white bread
¼ cup whole butter
½ cup Thousand Island dressing
1¼ cup arugula
2 each vine-ripened tomatoes, sliced into 8 slices
4 thin slices red onion

Rinse mushrooms and pat dry. Place in a glass dish in one layer, gill side up. Place the mustard, garlic and thyme in a small bowl; whisk in the vinegar and oil. Season with salt and pepper. Pour marinade over mushrooms and rub to coat well. Marinade at least one hour; turn, coat again and marinate another hour. Preheat oven to 375 degrees. Place the mushrooms on a baking sheet and bake until softened, about 15 minutes. Do not over cook; they should be only half done. Place mushrooms back in the marinade pan, rub to coat, season with salt and pepper and allow to cool. Dredge the mushroom in the flour, then into the egg, then coat with the breadcrumbs. Repeat with the other three mushrooms. Fry in a 360-degree deep fryer until golden brown and crisp. Place on paper towels to drain.

Meanwhile, heat an electric griddle or large sauté pan. Spread the butter on one side of the bread and place butter side down on the heat. Spread each slice with 1 Tbs. of Thousand Island dressing, and divide the arugula among four of the slices. Lay two slices of tomato on top of each pile of arugula, followed by the red onion. Finally, top with the mushroom and the second slice of bread. Transfer to a cutting board and cut in half. Serve immediately with pickles and cole slaw or homemade potato chips.