Julienne or grate the apple. Peel the kohlrabi and julienne or grate them. If grating, then take handfuls of kohlrabi and apple and squeeze out the excess moisture with your hands. Do this in batches. Lay the squeezed mounds on a paper towel and press down to remove remaining moisture. Add to a mixing bowl.
Add all the dressing ingredients to a small jar and shake to combine. Taste and adjust seasoning. Refrigerate until ready to serve the salad.
Dress the salad just before serving: pour the dressing over the kohlrabi and apples. Add raisins. Toss to combine making sure it’s evenly coated.