Preheating the oven to 400°F is required. Prepare a medium-rimmed baking sheet by lining its underside with foil. Before proceeding, line a baking sheet with foil and encase each beet in its foil. Bake for one hour in a preheated oven, or until the largest beet can be readily peeled. After allowing the beets to settle to room temperature and unwrapped, peel them before slicing them in half and wedges.
Toast 1/2 cup pecans on a dry skillet, stirring frequently until golden and fragrant. Discard from heat and allow to cool.
After transferring the arugula to a large mixing basin, combine the toasted pecans, dried cranberries, sliced beets, and feta cheese.