Peanut butter monster cookie bars

These cookie bars are the result of a little bit of mixing and matching some of my favourite ingredients. I love using peanut butter, especially with chocolate, and rolled oats always make things seem more nutritious. And, even though I’m not a massive fan of caramel, I was curious about the new caramel M&Ms. I thought they might have a gooey centre but they’re a firm caramel and they’re pretty darn tasty, and a nice little match to the peanut butter.

As far as I can tell, the name ‘monster cookie’ came about because they are like the Frankenstein of the cookie world – lots of different ingredients combined to make one cookie. Or it could be because the cookies all seemed to be monstrous in size, bigger than your hand. I decided to turn cookies into bars because sometimes you can’t be bothered scooping out cookies, you just want to press everything into a tin and shove it into the oven. Lazy people – it gets even better, because these are made in just one bowl. I was hoping the caramel M&Ms would melt and become gooey, but even after baking they stayed a nice firm caramel, which I think is a better result. These are a great little lunchbox filler because they’re sturdy and transportable, which means they’re also perfect for taking away during the fast approaching Christmas holidays.



150g butter, cut into pieces
120g peanut butter
220g rolled oats
300g flour
190g brown sugar
110g sugar
1 teaspoon baking soda
1 teaspoon salt
2 eggs
2 teaspoons vanilla extract
1½c chocolate chips
130g caramel M&Ms (here in NZ this is one packet)


Preheat the oven to 180°C and line a 9×13″ baking tin.
Put the butter in a medium heat proof bowl and microwave it until it is melted, around 40 seconds. Whisk in the peanut butter.
In the bowl of a stand mixer fitted with the paddle attachment, add all of the ingredients except the chocolate chips and M&Ms. Don’t forget to add the melted butter mixture.
Beat on low until everything is combined and a crumbly dough forms. Add the chocolate chips and mix again. (You can also do this by hand, it’s just easier in the mixer.)
Press the dough into the prepared tin and scatter over the M&Ms. Press them down into the dough.

Bake for around 20 minutes, or until the edges start to lightly brown.
Remove from the oven, and then while it’s still hot, press down the M&Ms again, as they will have risen with the dough.


Let it cool before cutting into squares. Store in an airtight container for up to one week.

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