Step 1Heat the oven to 375 degrees. Grease a 9-inch round by 3-inch tall cake pan and line the bottom with parchment paper.
Step 2In a medium bowl, whisk together the flour, cornmeal, baking powder and baking soda. In a separate medium bowl, whisk together the eggs, maple syrup, oil and vanilla. Set aside.
Step 3In the bowl of a stand mixer with the paddle attachment, or in a large bowl with a hand mixer, cream together the butter, 1 1/2 cups sugar, salt and zest. Mix just until thoroughly combined; do not overmix.
Step 4With the mixer running, slowly incorporate the egg mixture into the butter just until combined.
Step 5With the mixer on low speed, add one-half of the flour mixture to the batter and quickly mix for 5 seconds. Turn off the mixer and add the rest of the flour, the ricotta and one-half of the cranberries. Mix the remaining ingredients into the batter over low speed just until combined, being careful not to overmix.
Step 6Gently pour the batter into the cake pan and smooth the top. Scatter the remaining cranberries over the top of the cake, and sprinkle with the remaining 2 tablespoons sugar.
Step 7Bake the cake until a toothpick inserted comes out clean, about 1 hour and 15 minutes. Place a loose piece of foil over the top of the cake if it starts to darken. Cool the cake on a wire rack before removing it from the pan.