Arrange a rack in the middle of the oven and heat the oven to 425°F.

Remove the leaves from 1 medium head cauliflower. Cut in half and cut out the core. Break the florets into large (2-inch) pieces with your hands or a paring knife (about 7 cups); place on a rimmed baking sheet. Thinly slice 2 medium shallots (about ½ cup); place half on the baking sheet. Halve 1 large lemon.

Drizzle 2 tablespoons of the olive oil and sprinkle 1 teaspoon curry powder or smoked paprika, ½ teaspoon of the kosher salt, and ¼ teaspoon black pepper over the cauliflower. Toss until evenly coated and spread into an even layer. Place the lemon halves on the baking sheet cut-side up.

Roast until the cauliflower is tender and browned in spots, about 30 minutes. Meanwhile, prepare the remaining salad ingredients and make the seed crackle.

Pick the leaves from 1 medium bunch flat-leaf kale and discard the stalks. Tear or chop the leaves into bite-sized pieces (about 5 cups). Pick the leaves and tender stems from 10 fresh flat-leaf parsley sprigs (about 1 cup). Quarter 1 Persian cucumber lengthwise, then cut crosswise into ½-inch pieces (about ¾ cup).

Line a second baking sheet with parchment paper. Place 1 tablespoon of the water and 2 teaspoons of the honey in a small microwave-safe bowl and stir until the honey is dissolved. Add 2 tablespoons raw sunflower seeds, 2 tablespoons white sesame seeds, and the remaining ¼ teaspoon kosher salt, and stir to combine.

Microwave for 1 minute. Stir again, and microwave until fragrant and the seeds are toasted, about 30 seconds to 1 minute more. (Alternatively, place all the ingredients in a small nonstick skillet and cook over low heat until fragrant and the seeds are toasted, 5 to 6 minutes.) Immediately scrape onto the baking sheet with a flexible spatula and spread into an even, solid sheet about ⅛-inch thick.

When the cauliflower is ready, prepare the following, adding each to a large bowl as you complete it: Carefully scrape the lemon flesh into a large bowl, discarding any seeds. Finely chop the lemon skin. Finely grate 1 garlic clove.

Add the remaining 2 tablespoons olive oil, remaining 2 tablespoons water, 1 tablespoon sherry or red wine vinegar, 1 teaspoon Dijon mustard, remaining ½ teaspoon honey, and ¼ teaspoon kosher salt. Whisk to combine. Taste and season with black pepper and up to 1 tablespoon more vinegar as needed. Reserve 2 tablespoons for drizzling.

Add the kale, parsley, and cucumbers to the bowl of dressing, and toss to combine. Top with the cauliflower, then drizzle with the reserved dressing. Pick the leaves from 2 fresh mint sprigs and scatter over the salad, tearing if large. Break the seed crackle up into bite-sized pieces and scatter over the salad.