Preheat a dry skillet over medium heat. Add chopped walnuts and toast for 5 to 7 minutes, stirring frequently, until fragrant and lightly golden. Remove from heat and let cool completely.
Add the spring mix to a large salad bowl. Arrange the sliced pears, shallots, cranberries, crumbled feta, pomegranate arils, and cooled toasted walnuts over the top of the greens.
In a small mixing bowl or glass measuring cup, whisk together the olive oil, apple cider vinegar, honey, mustard, salt, and pepper until the dressing is smooth and fully combined.
Drizzle the dressing over the salad just before serving. Use salad tongs to gently toss everything together until evenly coated. Serve immediately.