Step #1 Preheat oven to 350F & spray a 9-10" springform pan with cooking spray.
Step #2 Place 1/2 c cornmeal, flour, baking soda, baking powder & 2/3 c brown sugar in a food processor/blender & pulse for a few seconds until well mixd.
Step #3 Add the lemon zest & butter & pulse until mixture looks like breadcrumbs.
Step #4 Add the egg & lemon juice & mix just until mixd.
Step #5 Put 2/3 of the mixture in the pan & press lightly to even it in the pan.
Step #6 Sprinkle top with 2 tsps cornmeal, the blueberries & the 2 tbsps brown sugar (in that order).
Step #7 Crumble the remaining cake mixture evenly over the top & press down lightly.
Step #8 Bake for 35 mins or until golden brown & a toothpick comes out clean.
Step #9 Cool for at least 20 mins before removing the sides of the cake pan.
Step #10 Serve warm with whipped cream or ice-cream, best served within 2-3 hrs of baking.