Place baking racks in the upper and lower thirds of the oven and preheat the oven to 425 degrees F. Line two rimmed baking sheets with foil. Brush the sheets with 1/2 tablespoon olive oil each. With a very sharp knife, slice the sweet potatoes into 1/2-inch slices. Arrange the slices in a single layer on the oiled baking sheets, then brush the tops with the remaining 1 tablespoon olive oil. Sprinkle with salt and black pepper. Bake for 15 to 20 minutes, until golden brown underneath, rotating the pans 180 degrees and changing their positions on the upper/lower racks halfway through. Remove the pans from the oven, flip the slices over, then roast for an additional 5 to 8 minutes, until tender.
While the potatoes bake, in the bottom of a small mixing bowl, whisk together the vinegar, Dijon, and maple syrup. Finely chop the pecans, shallot (you should have about 1/4 cup), apple (no need to peel; you will have about 1/3 cup), and cranberries. Add them to the bowl with the dressing and sprinkle with the rosemary. With a rubber spatula, toss to coat with the dressing, scraping the spatula along the bottom of the bowl so that the ingredients are well moistened. Fold in half of the goat cheese.
When the sweet potatoes are finished, let them cool slightly, then transfer them to a serving plate. Top with the pecan mixture, then sprinkle with the remaining goat cheese. Enjoy immediately.
The topping can be prepared up to 1 day in advance and stored in the refrigerator. You can also roast the potato rounds in advance, then rewarm them in an oven just before serving. The bites will soften as they sit but taste great at room temperature, even if they are a bit soft.
Sorry to leave you with the odd half of an apple left over! I usually try to avoid this, but the whole apple was just too much (and it was too yummy WITH the apple to omit it entirely). I suggest you snack on the remaining half while the bites bake...or save it for these Apple Cinnamon Overnight Oats.