Preheat oven to 425°F and line a baking sheet with parchment.
Toss sweet potatoes with 2 tablespoons olive oil, kosher salt, and black pepper on the sheet pan until evenly coated.
Spread in a single layer with space between cubes.
Roast 25 to 30 minutes, flipping once, until tender with deeply browned edges.
While potatoes roast, whisk apple cider vinegar, Dijon, honey, smoked paprika, salt, and pepper in a small bowl.
Slowly drizzle in the ⅓ cup olive oil while whisking until emulsified.
Remove potatoes from oven and let rest 5 minutes, until warm but not hot.
In a large serving bowl, combine mixed greens, apple slices, pecans, and cranberries.
Add warm sweet potatoes and drizzle lightly with vinaigrette, tossing gently to coat without soaking.
Scatter crumbled goat cheese or feta over the top and serve immediately.