Wash kale leaves and dry thoroughly. Trim leaves from the thick stems (discard stems). Rip leaves by hand into smaller pieces or chop as desired. You should have approximately 8 loosely packed cups of trimmed leaves. Place in a large mixing bowl.
To the kale, add the olive oil, lemon juice, salt, black pepper and garlic. Toss to combine.
Add the Parmesan cheese, currants and walnuts (pine nuts if using) and toss all ingredients together.
Let the salad rest for at least one hour, allowing all of the ingredients to mellow and meld together and for the kale leaves to soften slightly. Plate and serve.