Preheat your oven to 400°F (200°C).
Toss the sweet potato pieces with 2 tablespoons of olive oil and ½ teaspoon of kosher salt, then spread them out on a baking sheet.
Roast the sweet potatoes in the oven for about 25-30 minutes, or until they are tender and slightly caramelized.
While the sweet potatoes are roasting, prepare the dressing by whisking together the tahini, lemon juice, Dijon mustard, honey, black pepper, grated garlic, and the remaining olive oil and kosher salt in a bowl.
Gradually add the water to the dressing until you reach your desired consistency.
In a large bowl, combine the chopped kale and the roasted sweet potatoes once they are done.
Pour the dressing over the kale and sweet potatoes, and toss everything together until well coated.
Add the chopped dates, walnuts, and grated Parmesan cheese, mixing gently to combine.
Serve the salad immediately or let it sit for a few minutes to allow the flavors to meld.
