From How to Cook Everything Vegetarian by Mark Bittman
* You can also use collards, spinach (squeezed and chopped), broccoli, cauliflower, cabbage, and mushrooms
Ingredients:2 tablespoons butter, plus more as needed
About 8 large kale or collard leaves, thinly sliced
1 medium onion sliced
Salt and freshly ground black pepper
1/4 cup chopped mixed herbs, like parsley, thyme, chervil, and chives
1 cup whole milk yogurt or sour cream
3 tablespoons mayonnaise
1/2 teaspoon baking powder
1 1/4 cups all-purpose flour
1. Preheat the oven to 375 degrees F. Put the butter in a large skillet, preferably non-stick, over medium heat. A minute later, add the kale and onion. Sprinkle with salt and pepper and cook, stirring occasionally, until the leaves are quite tender, about 10 minutes; do not brown. Remove from heat, add the herbs, then taste and adjust the seasoning.
2. Meanwhile, hard-cook 3 of the eggs, then shell and coarsely chop. Add to the cooked kale mixture and let cool while you make the batter.
3. Combine the yogurt, mayonnaise, and the remaining eggs. Add the baking powder and the flour and mix until smooth. Lightly butter a 9 x 12-inch ceramic or glass baking dish. Spread half the batter over the bottom, then top with the kale filling; smear the remaining batter over the kale, using your fingers or a rubber spatula to make sure there are no gaps in what will form the pie's top crust.
4. Bake for 45 minutes; it will be shiny and golden brown. Let the pie cool for at least 15 minutes before slicing it into as many squares or rectangles as you like. Eat warm or at room temperature.