The curry powder in the dressing and the shallots and apricots make this a special salad.
Place chicken in a shallow 2-quart microwave-safe dish with a lid; season with salt and pepper. Cover, and microwave on high until opaque throughout, 10 to 12 minutes, turning chicken halfway through. Let cool briefly; slice crosswise.
In a serving bowl, whisk vinegar, oil, Dijon, honey, and curry powder; season with salt and pepper. Add spinach, shallots, and apricots, and toss.