How to Make It
Preheat oven to 450ºF. Stir together breadcrumbs, 2 tablespoons of the oil, 1/2 teaspoon of the garlic, and 1/4 teaspoon of the salt in a medium bowl; set aside.
Heat remaining 2 tablespoons oil in a Dutch oven over medium-high. Add onion, and cook, stirring often, until softened, about 5 minutes. Add remaining 1 teaspoon garlic, and cook 30 seconds. Add kale, collards, and 3 tablespoons water. Cook, stirring often, until greens are wilted and tender, 10 to 12 minutes. Add cream cheese, fontina, half-and-half, black pepper, remaining 1 teaspoon salt, and (if desired) crushed red pepper. Cook, stirring constantly, until just heated through, about 8 minutes.
Transfer to a lightly greased (with cooking spray) 2-quart baking dish, and sprinkle with breadcrumb mixture.
Bake in preheated oven until golden and bubbly, about 15 minutes.