Heat a medium skillet over medium heat. (Do not add any fat to the pan!) When hot, add the pepitas and toast, shaking the pan occasionally, for about 3 minutes or until lightly browned and fragrant. Transfer to a plate or bowl to cool.
Add the kale to a large mixing bowl. Drizzle with 1 tablespoon of olive oil and season with a good pinch of salt. Massage the kale in handfuls—literally rub the leaves between your fingers—for a minute or two, until the leaves soften and darken in color. (Yes, I know giving your salad a rubdown is a little weird, but it’s worth it. DO NOT SKIP THIS STEP.)
In a medium bowl, whisk all of the ingredients for the dressing. Add the apple to the dressing and toss to coat. (The lemon juice in the dressing will help prevent the apples from browning in the salad.)
Add the apple, dressing, Brussels sprouts, raisins, and cooled pepitas to the bowl with the kale and toss to combine. Taste and season with a little extra salt, pepper, or lemon if needed. Serve at room temperature.