Preheat oven to 350 and grease the bottom of a 9x13”pan.
In a large bowl combine eggs, oil, water and cake mix. Beat on low speed for 30 seconds, then medium speed for 2 minutes until it’s thoroughly combined.
Pour into prepared pan and bake according to directions on box.
Let the cake cool.
Use a round cookie/doughnut cutter and cut out pieces of the cake.
Layer cake and cool whip into large Mason jars and top with blueberries.
Recipe by Purely Katie at https://www.purelykatie.com/easy-red-velvet-trifle/