Cook pasta according to package directions.
While pasta is cooking, prepare dressing: In a food processor or small blender combine the oil, vinegars, sugar and spices. Pulse for about 10 seconds. Stir in poppy seeds.
Drain cooked pasta, rinse with cold water, and set aside.
Combine spinach and chopped celery in a large bowl. Add in the cranberries and can of drained mandarin oranges.
Cut apple into thin slices, toss with lemon juice, and add to the salad.
Pour dressing over the salad and toss. Add in the cooled pasta and toss with the rest of the salad.
Top salad with pecans (toast if desired) and feta cheese.