Lemon Blueberry Cake

This cake was very easy to make.  I got help from a lemon cake mix.  I thought adding blueberry would elevate it.  I cooked down a cup of frozen blueberries with 2 tsp of sugar for about 10 minutes on medium high heat, mashing while I stirred.  I took it off the heat to let cool and followed the directions on the cake mix box. Once the cake was in the pan, I spooned the blueberries over the batter and used a toothpick to swirl the blueberry into the cake. I baked according the the box directions and this is what I got: