Heat the oil in a medium skillet on medium-high heat, add the sourdough cubes, and saute.

Make sure to stir or constantly shake, so the croutons are evenly cooked and begin to brown on all sides. Set aside.

Combine the tahini, olive oil, lemon juice and zest, water, garlic, mustard, 1/4 cup cheese, salt, and pepper in a blender or mini food processor and process until smooth. (Makes about 1 1/2 cups).

To grill the romaine, preheat a grill over medium- high heat. Slice the romaine hearts in half vertically. Using a pastry brush, brush the cut side of each heart (you should have 6) with olive oil, then season with salt and pepper.

Using tongs, place the romaine onto the grill, cut- side down. Grill 2 minutes or until lightly charred. Flip and grill for another 1 to 2 minutes, until they collapse a little - then remove to a platter.

Drizzle the dressing over the lettuces and top with the croutons, capers, 1/4 cup parmesan cheese, and freshly ground black pepper.