Heat the olive oil in a 10 or 12-inch oven-safe skillet over medium heat. Add the cumin seeds and let them sizzle gently for 1 to 2 minutes, or until fragrant. Add the kale in batches, letting each handful shrink and wilt before adding the next.
When the last of the kale has wilted, add the tomato sauce, chickpeas, lemon juice, and ½ cup water. Stir and let it come to a simmer.
Nestle the feta slices into the sauce and sprinkle with freshly ground black pepper. Slide the skillet into the oven and bake until the feta has softened, about 15 minutes. Drizzle with olive oil and sprinkle with the red pepper flakes. Garnish with parsley and serve with pita and lemon wedges.