Spicy radishes and radicchio stand up beautifully to the hearty flavor of this creamy dressing, made from roasted green onions, silken tofu, and white-wine vinegar. Fire up the grill to cook the onions, if you prefer.
Preheat the oven to 450 degrees. Roast onions on a baking sheet until tender and golden brown, 10 to 15 minutes; let cool.
In a blender, purée onions, tofu, 2 tablespoons almonds, tamari, vinegar, and 2 to 3 tablespoons water until very smooth. In a large bowl, toss plums, radicchio, lettuce, carrots, radishes, remaining almonds, and dressing, and then serve.