A polenta gratin is basically a baked casserole made with cornmeal mush and cheese. Of course, most cooks add more to this dish than those two ingredients, making for a wide range of polenta gratin recipes. Polenta is a food eaten in many parts of the world, meaning it combines rather well with many different kinds of flavors and foods. Any cook with a batch of polenta on hand and some delicious cheese should be able to whip up one of these gratins with little more than some odds and ends already present in the cupboard. Creating a perfect dish can be tricky, but it is usually less work than making a potato gratin.
Every polenta gratin recipe starts with some kind of polenta. Fresh store-bought versions can usually be found in the refrigerated section of a grocery store, and are usually shaped like bricks. Instant polenta comes in boxes generally sold next to packages of instant potatoes. Simply put, polenta is little more than cornmeal mixed with boiling water. It is stirred until it becomes thick, like pudding or porridge. Cooks using instant polenta usually notice that the cornmeal soaks the water up very quickly. Fresh polenta is already boiled and can usually be mashed with a fork after the package is opened.
Cooks who enjoy creating and experimenting may quickly fall in love with a polenta gratin because the polenta itself is a blank slate. These recipes usually call for the cook to mix the polenta with one or more kinds of cheese, some spices, and, sometimes, vegetable puree. For instance, a recipe might instruct the cook to add shredded fontina, Gruyere, and parmesan cheeses to the polenta, along with pumpkin puree, garlic, and chopped mushrooms. This mixture would then be spread evenly over the bottom of a greased casserole dish and baked.
The top of a polenta gratin is often crusted with the veggies mixed into the casserole. The cook generally cuts 0.25 inch (about 0.5 cm) slices of the veggies and lays them in neat rows on top of the polenta. The rows usually overlap and the slices are generally circular. This makes squash an ideal veggie to include in these recipes. The cook can chop up the body of the squash to flavor the polenta and slice the neck to give it a tasty crust.
While dessert polenta gratin is rare, it can be a tasty and nutritious way to end a meal. Some cooks also like to make it for breakfast. The versatile polenta can be flavored with sugar, cinnamon, and mascarpone cheese. The slices for the top of the casserole could be of pears, apples, or peaches. Cooks with more time might even coat the top with sliced and pitted cherries.