POLENTA:
2 tablespoons butter (plus more for greasing the pan)
1 tablespoon minced fresh garlic
2 cups whole milk
2 cups water
1 teaspoon salt
  pinch Freshly ground black pepper
  pinch red pepper flakes
1 cup polenta (corn grits)
 
  KALE SAUTÉ: (makes about 5 cups)
3 tablespoons olive oil
1 medium yellow onion (cut in half through the stem end, then thinly sliced crosswise, about 2 cups)
1 pound Dino (lacinato) kale (stems discarded, leaves cut crosswise into 1-inch-wide ribbons, about 12 cups packed)
3 cloves garlic (large cloves, finely minced)
 
1/4 cup Whole wheat pastry flour or corn flour
  Safflower or sunflower oil (or another high-heat oil)
4 cups marinara sauce (homemade or good-quality store bought)
  Freshly grated Parmigiano Reggiano cheese (optional, as garnish)