The 70s was the era of poke cakes! Jell-O's sales campaign made it popular with busy housewives.
Mix the cake mix and other ingredients listed on the box in a large bowl using a hand mixer. Beat on low speed for 30 seconds, then beat on medium speed for 2 minutes.
Bake the cake mix according to the package instructions in a 13×9-inch cake pan. Remove the baked cake from the oven and allow it to cool for 15 minutes.
Poke small holes all over the top of the cake with the handle of a wooden spoon or a chopstick.
Pour gelatin over the cake slowly, ensuring it fills all the holes. Refrigerate for at least 3 hours or overnight.