Corn is a quintessential ingredient in dishes throughout Latin America. This casserole is less dense and more soufflé-like than similar versions made in the American South, but still has a flavor that's sure to please a crowd. It can be served as a main or side dish.
Heat the oven to 350º. In a small frying pan over medium-low heat, melt the butter and warm the oil. Add the onions and sauté until soft, stirring occasionally so they don't brown, about 10 minutes. Remove the pan from the heat and allow the mixture to cool until lukewarm.
In a large bowl, mix the cornmeal, salt, sugar, and baking powder, and set the mixture aside.
In a blender or food processor, puree the corn with the milk. Blend in the egg yolks and then combine this mixture, along with the cheese and onions, with the dry ingredients.
In a separate bowl, beat the egg whites until stiff but not dry. Carefully fold the egg whites into the corn mixture, and then pour it into a 7- by 11-inch buttered and floured baking dish.
Sprinkle the casserole with the Parmesan and bake it in the middle of the oven until golden brown, about 45 minutes. Allow it to cool for a few minutes before slicing and serving. Serves six as a main dish, 12 as a side.
Per serving (1 piece, 12 pieces per recipe): Calories 211 • Total Fat 13 g • Saturated Fat 6 g • Cholesterol 74 mg • Sodium 308 mg