I have this recipe from Gourmet Grains, Beans and Rice for Polenta Crust I have tried it and it can be a finger food. It is firm. Polenta is made of cornmeal. Here it is:

Spray a 9 inch pie pan with nonstick spray. Preheat oven to 375. Place cornmeal in a small bowl. Add cold water and stir until well mixed. Stir cornmeal mixture into saucepan of boiling water. Cook, stirring over low heat until thickened, 3 to 5 minutes. Remove from heat and stir salt and Parmesan.

Spread cornmeal mixture to form a crust in the greased pan, using wet hands or a spatula. Spread evenly across bottom and up sides. Bake uncovered for 30 miutes.

I make this crust on a rather large square pan and do not shape into a pie, I, then cut into squares.

Toppings can consist of sauteed green and yellow peppers , mushrooms , etc.