Begin by peeling and dicing sweet potatoes. Bring a large pot of salted water to a boil over high heat. Add the potatoes, reduce heat and cook until just tender but still have a little bite. Drain and place in a bowl to cool.
Combine the dressing ingredients in a blender and puree until smooth. Season with salt and pepper. Once potatoes are cool toss with dressing and set aside on salad platter.
Combine ingredients in a large mixing bowl and dress with lemon juice, olive oil, to taste, a splash of soy sauce, and a little salt and pepper. Toss well and place on top of the sweet potatoes to serve as a complete salad.