Preheat the oven to 350°F and grease an 8-inch square baking pan.

Whisk the brownie mix with the oil, water and one egg (or whichever ingredients are listed on the packaging) until everything is well combined.

Whisk the cream cheese, milk and the other egg in another bowl.

Now add the banana pudding mix to the other mix, and combine until everything is smooth.

Put ½ the brownie mix in the greased baking pan and dollop on the banana mixture on top.

Swirl the mixtures together using a chopstick, skewer or butter knife.

Add the rest of the brownie mix and then the rest of the banana mixture, and swirl some more.

Add 9 wafers on top, pressing down a little, so when you cut the brownies each one will have a cookie in the center.

Bake for however long it says on the brownies mix packaging, adding 5 minutes extra.

Put the baking dish on a cooling rack and let the brownies cool completely.

Refrigerate for at least half an hour before cutting them up.