In a large bowl, stir together the dry cake and the entire can of crushed pineapple with its juice. Stir well until all the dry mix is incorporated. (The mixture will get really foamy.)
Pour the batter into a 9x13 pan which has been lightly greased with nonstick cooking spray.
Bake at 350F degrees for time specified on the box for size pan. When the sides pull away from pan and toothpick inserted in the center comes out clean, the cake is done. This should take somewhere between 30 and 40 minutes.
Remove from the oven and place on a wire rack to cool.
Notes
Serving size: 1 piece of cake without additional toppings (1/12th recipe)WW Points: 8Check the WW Points for this recipe and track it in the WW app. (Must be logged into WW on a smartphone or tablet.)7SmartPoints (Green plan)7SmartPoints (Blue plan)7SmartPoints (Purple plan)4PointsPlus (Old plan)Be sure to use the 1-step angel food cake mix, like the one from Betty Crocker, that says, "just add water."And you'll want a 20-ounce can of crushed pineapple in juice (not heavy syrup).Store your pineapple cake for up to 5 days in the refrigerator, covered with plastic wrap or in an airtight container.Cake slices can be frozen for up to 2 months. Wrap pieces individually in plastic wrap and place them in a freezer-safe container or plastic bag.