How to Make It
Preheat the oven to 400°. Cut three-quarters of the cauliflower into 2-inch florets. Thinly slice the remaining cauliflower and reserve.
On a rimmed baking sheet, combine the cauliflower florets with 2 tablespoons of the olive oil, the thyme and garlic; season with salt and toss to coat. Spread the cauliflower in an even layer and roast for 25 to 30 minutes, stirring halfway through, until golden and tender. Discard the thyme and garlic. Sprinkle the cauliflower with the lemon zest and 1 tablespoon of the lemon juice, season with salt and toss to coat.
Meanwhile, in a medium bowl, whisk the remaining 1/2 cup of olive oil and 3 tablespoons of lemon juice with the vinegar and capers until emulsified. Season with salt and pepper.
In a large bowl, combine the kale with 1/4 cup of the dressing and mix, gently massaging the kale to tenderize it. Add the arugula and another 2 tablespoons of the dressing and mix well.
Arrange the roasted cauliflower on a platter and top with the radishes, cherries, greens and the reserved raw cauliflower. Spoon on the remaining dressing, scatter the pepitas on top and serve.