Do not make cake mix according to box directions. Combine cake mix, instant pudding, melted butter, milk, water and eggs using a mixer. Fold in blueberries and mix with spoon. Spray a 10 inch bundt pan with cooking spray.
Pour in batter and bake in preheated 350 degree oven for 50 to 55 minutes until center tests done. Remove and let cool 10 minutes before removing from pan. Makes 1 bundt cake. Enjoy!
You can also make this cake without the blueberries and add a lemon glaze!
Whisk together and drizzle over cake. You can also just sprinkle on powdered sugar if you don't want a glaze or leave it plain.
You could probably use any lemon cake mix and frozen blueberries should work if drained well. You could also make this in a 9 x 13 pan but I would check center after about 40 minutes to see if done.