Got this recipe out of a Deborah Madison (swoon!) cookbook called This Can't Be Tofu.
Bachelor Tofu Sandwiches
1 carton firm tofu, drained
4 teaspoons olive oil, divided
2-3 tablespoons Worcestershire sauce
Salt and freshly ground black pepper
1 large red or yellow onion, cut into 14-inch slices
4 big mushrooms, sliced as thick as the onions
8 slices bread
Mustard and horseradish
Slice tofu crosswise into 8 pieces, slightly less than 1/2-inch thick. Set them on paper towels and blot. Don't worry about the tofu getting really dry. It will dry as it cooks.
Heat a large cast-iron skillet. Brush with 2 teaspoons of the oil and add the tofu. Cook over medium-high heat until golden, about 6 minutes on each side. Douse with the Worcestershire sauce and turn the tofu once. Continue frying until the sauce is absorbed and the tofu is laced with a fine glaze. Turn off the heat and season well with salt and plenty of pepper.
While the tofu is cooking, place a 10-inch skillet over high heat and add the remaining 2 teaspoons oil. Add the onion and mushrooms. Saute until seared and nicely browned, 5-7 minutes. Season with salt and pepper.
Toast the bread if desired. Cover with mustard and horseradish (fresh tomatoes and mayo would be good here as well). Add the tofu slices, top with the onions, close, press and dig in.
This sandwich was surprisingly good, even though there's nothing green in it, which usually is part of my definition for a good sandwich. I used four slices of tofu on mine, and portobellos, which made it a pretty substantial deal. Very easy, and super quick ... I would definitely make it again. I also think it can be hard to envision tofu working in a sandwich, but this makes the cut.