Preheat the oven to 400°F (200°C) and line a baking sheet with parchment paper.

Place the grapes on the baking sheet, drizzle with 1 tablespoon of olive oil, sprinkle with salt, and roast for 15-20 minutes until blistered.

While the grapes roast, wash and dry the kale. Remove tough stems and tear leaves into pieces.

In a large bowl, add the remaining olive oil and balsamic vinegar to the kale. Massage the leaves until tender.

Once roasted, combine the grapes with the massaged kale, feta cheese, and toasted walnuts. Toss gently.

Serve immediately, drizzled with additional balsamic vinegar if desired.