Preheat oven to 375 degrees and spray the bottom of a 8 or 9 inch square baking pan with non-stick cooking spray.  Open and drain the can of blueberries from inside the box of muffin mix. Set aside.

In a bowl, mix together the muffin mix, water, oil, and egg just until combined.  The batter will be lumpy.

Gently fold in the lemon rind and blueberries into the batter.  Pour batter into the prepared baking dish.  Bake for 23-30 minutes until top starts to get golden and toothpick inserted in the center comes out clean.  Allow to cool for 10 minutes.

In the meantime, combine the powered sugar and lemon juice together to created a glaze.  Drizzle the glaze over the coffee cake after it has cooled for the 10 minutes and serve.