Spray a 9/13 inch baking dish with nonstick spray.
In a large bowl, mix the pudding milk with milk. Whisk until fully combined. Use a large spoon or whisk to add in the cake mix until fully incorporated and smooth. The mixture will be quite thick, which is fine. Stir in the chocolate chips. Set aside.
In another large bowl, mix together the strawberries, banana, pineapple, and sugar. Stir to combine and let macerate for at least 5 minutes.
When ready to make the cake, pour the fruit into the bottom of the baking dish, making a thin layer.
Top with the cake mix and spread with a spatula or spoon to create a smooth top.
Bake for 45-60 minutes or until the cake is completely cooked through (when a toothpick inserted in comes out clean).