Preheat the oven to 350°F.
Place the eggs, sugar and oil in the bowl of an stand mixer with the whisk attachment, or place in a large mixing bowl and prepare a handheld electric mixer. Beat them together on medium speed for one minute, until light and foamy.
In another large bowl, whisk together 2 cups of the flour with the cornmeal, salt, baking powder and cinnamon until thoroughly blended. Add the dry ingredients to the wet ingredients and beat them together until a thick dough is formed. Use a spatula to fold the remaining 1/4 cup of flour into the dough by hand. Let the dough sit for five minutes so the flour can absorb the moisture from the eggs.
Meanwhile, lightly grease a cookie sheet with non-stick vegetable spray, line it with parchment paper, and lightly grease the parchment (or simply place a Silpat liner on your cookie sheet, no grease needed).
Flour your bench and your hands, and divide the dough in half. Roll each half into a log about 1 1/2 inches wide. Place the logs on the prepared cookie sheet, evenly spaced. The dough will be tacky, but should be easy to manage; you can continue to shape the logs after placing them on the cookie sheet.
Use a pastry brush to remove any excess flour. If you want to add a bit more sweetness to the toasts, brush them with the optional milk and sprinkle the optional sugar on top.
Bake the logs for 20 to 25 minutes, or until they are puffy, golden brown and firm to touch. Remove the cookie sheet from the oven and turn the temperature down to 300 degrees. Let the logs cool for 15 minutes on the tray.
Use a serrated knife to slice the logs on the bias about 1/2 inch thick. Lay the biscotti flat (on one of the cut sides) on the cookie sheet. Return the slices to the oven and bake for an additional 15 to 20 minutes, or until the slices are browned and toasted. Allow the toasts to cool completely and store them in an air-tight container.