Place the bulgur in a large bowl and pour the water over it. Wrap with plastic wrap and allow to steam until the bulgur has absorbed most of the water, about 20 minutes. Strain the bulgur through a fine-mesh strainer, pushing as much of the water out of the bulgur that you can, and return the bulgur to the bowl. Add the tomatoes, cucumber, parsley, mint, green onions, salt and pepper to the bowl and toss with a fork to blend. In a small bowl, whisk together the olive oil and lemon juice and drizzle over the tabbouleh salad. Stir to blend.

Place the tabbouleh in a decorative bowl and line the edges with romaine lettuce leaves that have been halved. Serve at room temperature or chilled.