Preheat the oven to 350 degrees F (175 degrees C). Grease and flour a 9x13-inch baking pan.
To make the cake: Stir cake mix and instant pudding together in a large bowl. Add water, oil, and eggs; mix until smooth and well blended. Spread batter evenly into the prepared pan.
Bake in the preheated oven until a toothpick inserted comes out clean, about 40 to 45 minutes. While cake is still hot, poke holes in the top with a fork.
To make the sweet lemon glaze: Mix lemon juice and confectioners sugar together in a small bowl until smooth; pour over hot cake and allow to seep into the holes. Let cake cool completely before serving.
Notes
Serve with whipped topping or vanilla ice cream for added flavor.