Preheat the grill to medium-high heat.
Place the mushrooms in a baking dish
or pie plate
together the vinegar, oil, salt and pepper until blended. Brush the mushrooms with the vinegar mixture; let stand for up to 15 minutes.
Place the mushrooms on the grill rack and grill
until tender, 4 to 6 minutes per side. Transfer to a plate.
Meanwhile, combine the yogurt, rosemary
and juice of the lime
in a small bowl until blended. Brush the bread slices with the yogurt
mixture. Layer half the slices with the mushrooms, arugula, tomatoes
and red pepper strips. Top with the remaining bread slices. Serve immediately.