Toss kale with oil and lemon juice in a medium bowl; season with salt and pepper. Massage dressing into kale with your fingers and let sit at room temperature 2 hours to soften (this will keep kale from getting too crispy when baked).
Place a rack in lower third of oven and preheat to 525° or as high as oven will go.
Once dough has risen in baking sheet, top with mozzarella, dot with ricotta, and top with kale and Parmesan. Bake until golden brown and crisp on bottom and sides, 20–30 minutes.
Serve topped with red pepper flakes.