Set bulgur wheat in a bowl and cover with water; let stand for 20 minutes. Meanwhile in a mixing bowl combine sesame and vegetable oils with ginger, garlic, lemon zest and juice and season well to taste with salt and crushed red pepper. Drain the bulgur and squeeze out as much water as you can with your hands. Combine bulgur with dressing, mint, cilantro and scallions. Fold in the jicama and adjust seasoning; serve over watercress and Boston lettuce.