How to Make It
Heat the olive oil in a large heavy saucepan. Add the onion and garlic and cook over moderate heat, stirring occasionally, until softened, about 6 minutes.
Add the chicken stock, 1 1/2 cups of water and 1 teaspoon coarse sea salt and bring to a simmer over moderately high heat. Whisk in the polenta in a slow, thin stream, whisking constantly so that no lumps form. Cook, stirring frequently in the same direction with a flat wooden paddle until the polenta is fairly thick, 25 to 30 minutes. Stir in the butter, thyme and Parmesan cheese. Season with salt and pepper and remove from the heat. Serve hot.