How to Make It
Heat a medium saucepan over moderate heat. Add the sorghum and cook, stirring constantly with a wooden spoon, until the grains pop, about 3 minutes. Once the popping stops, transfer to a plate to cool. Sprinkle lightly with salt.
In a large serving bowl, whisk together the orange juice, lemon juice, shallot, soy sauce, Dijon mustard, ginger, and honey. Gradually whisk in the oil in a slow, steady stream until emulsified. Season with salt and pepper. Add the spinach, cucumber, and red onion, and toss. Top with the popped sorghum, and serve.