Preheat the oven to 350?F (175?C). Grease and flour a 9x13 inch baking pan.

In a mixing bowl, combine the yellow cake mix, eggs, water, and vegetable oil. Mix until smooth.

Pour the batter into the prepared baking pan and bake for 30 minutes or until a toothpick inserted in the center comes out clean.

In a saucepan over medium heat, combine the blueberries, lemon juice, and sugar. Cook until the blueberries burst and the mixture thickens, about 5-7 minutes.

Remove from heat and let cool slightly.

Once the cake is baked, remove it from the oven and let it cool for 10 minutes.

Using a toothpick, poke holes all over the top of the cake.

Pour the blueberry lemon sauce over the cake, making sure it seeps into the holes.

Allow the cake to cool completely before topping with whipped cream, additional blueberries, and lemon zest.