Step 1

Prepare and bake the cake mix according to package directions for baking in a 9x13 pan.

Step 2

Cool in the pan for 15 minutes. Using the handle of a wooden spoon, poke holes all over the cake going all the way down to the bottom.

Step 3

Combine the pudding mix and cold milk in a large bowl. Whisk for two minutes. Pour half of the pudding over the cake so that it runs down into the holes made with the spoon.

Step 4

Let the remaining pudding stand for 5 minutes so that it thickens. Pour the remaining pudding over the cake and spread evenly over the top.

Step 5

Top the cake with marshmallows and refrigerate for at least 1 hour.

Step 6

When ready to serve, remove cake from refrigerator and heat the broiler. Place the cake in the oven and broil until marshmallows are golden brown, 1 to 2 minutes.

Step 7

Cut into squares to serve.