Add the dressing ingredients to a small bowl or a measuring cup that holds at least two cups. Whisk together until the sugar is dissolved and set aside.
Salad
Chop your lettuce and add your spring mix to a large bowl.
Chop the apple into small pieces. Add them to the bowl along with cranberries and pecans.
Whisk your dressing one more time before serving the salad with feta cheese.
Notes
You can make the dressing and the salad ahead of time. Store the dressing in an airtight container or mason jar, and put all the salad ingredients except the cheese in a large tupperware. Any leftovers can also be stored this way for up to 5 days.