Preheat your oven to 400°F (200°C).
Prepare the kale by removing the tough stems and tearing the leaves into bite-sized pieces.
On a baking sheet, toss the orange segments with a drizzle of olive oil and roast for 15-20 minutes.
Add the kale to the same baking sheet and drizzle with olive oil, salt, and pepper.
Roast the kale with the oranges for an additional 10-15 minutes until the kale is tender.
Meanwhile, in a small bowl, whisk together the olive oil, apple cider vinegar, honey, salt, and pepper.
Add the roasted kale and oranges to a large bowl, followed by the chopped walnuts and torn prosciutto.
Drizzle the dressing over the salad and toss gently to combine.
Serve immediately, garnished with extra walnuts if desired.