Step 1

Place a rack in upper third of oven; preheat to 425°. Finely grate half of garlic into a large bowl. Mix in lemon zest, 3 Tbsp. oil, 2 tsp. Diamond Crystal or 1¼ tsp. Morton kosher salt; season with pepper. Pat chicken dry and place in bowl, turning and rubbing to evenly coat.

Step 2

Cut squash in half lengthwise; scoop out seeds and discard. Slice crosswise 1” thick. Place squash and Halloumi on one half of a large rimmed baking sheet. Drizzle 1 Tbsp. oil over, finely grate remaining garlic on top, and sprinkle cumin and 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt evenly over. Season with pepper and toss to combine. Arrange into an even layer, keeping to the same side.

Step 3

Place shallot slices in 6 piles on other half of baking sheet; top each pile with a chicken thigh, skin side up. Roast until chicken is cooked through and squash is fork-tender, 33–36 minutes.

Step 4

Heat broiler. Broil vegetables and chicken until skin is golden brown and crisp, about 2 minutes.

Step 5

Meanwhile, whisk lemon juice, mustard, syrup, remaining ½ tsp. Diamond Crystal or ¼ tsp. Morton kosher salt in a clean large bowl; season with pepper. Gradually stream in remaining ⅓ cup oil, whisking until emulsified. Add kale; massage dressing into greens.

Step 6

Transfer chicken to a cutting board; thinly slice, discarding bones. Transfer to bowl with salad; add squash, Halloumi, and shallots and toss. Season with pepper.