Giant chocolate chunk cookies with spelt, oat and olive oil

"How big should we make the cookies?" I asked my daughter, as I took a bowl of chilled cookie dough from the fridge.

"REALLY big," she replied, with outstretched arms. And so we started rolling generous portions of dough into balls, then squashing them flat with the palm of our hands.

While in the oven I watched the cookies spread wider and wider, and wondered whether we had perhaps made them too big.

Everyone has their own preferences when it comes to chocolate chip cookies. For this recipe I made batch after batch until I achieved the precise texture I desired — thin, chewy, chocolatey and with crisp edges.

Inspired by Robyn from Sweetish Co., I used both oat flour (by blitzing rolled oats in a food processor — see tips below) and spelt flour. While experimenting, I learnt that even a slight change in flour variety and quantity can greatly alter the texture of your cookie. Similarly, you need a certain amount of sugar to get that desired texture; so, while you might be tempted to cut the quantity down, I would warn against doing so here. 

Giant cookies are a delight to eat, though they do require a bit of care to ensure they bake-up nicely.

You'll need to squash them before baking to ensure you don't end up with burnt edges and an under-cooked middle.

You'll also need to bake just one tray at a time, while ensuring the cookies aren't overcrowded. I think it's worth the effort, though. If only for the look on my son's face when he sees them.

Tips:

• While it's tempting, avoid sugar substitutions: Brown sugar may also be called light brown sugar, depending on where you live. Unfortunately, you cannot swap the brown sugar for white sugar in this recipe, as the texture would be too greatly altered.
• Choosing olive oil: use an extra virgin olive oil that has a nice flavour, but not the highest quality, first pressed variety.
• DIY oat flour: I blitz my rolled oats in a food processor to make a semi-fine flour. I make sure to not over-process them — a bit of rough texture is necessary. 
• Flour substitutions tips: you can try playing around with different flours here, however keep in mind that flours behave quite differently (for example, some absorb more liquid than others), and so even a slight change in variety or quantity can greatly alter the texture of your cookies.
• If you are still keen to try the two options below, I would recommend reducing the total flour quantity by 10g (leaving you with a total of 80g flour instead of 90g), as this might help give you a thinner, crispier texture. Similarly, you can try using plain flour in place of spelt but, again, this will alter the texture and give you a different cookie.
• Using GF flour: If you are after a thin, chewy cookie (like the ones in this recipe) using gluten-free flour, I have had success swapping the 50g spelt flour for 40–45g buckwheat flour, however, you will need to leave the cookies on the baking tray to cool for a while before transferring to a wire rack (otherwise they might fall apart). If you're baking for those with coeliac disease it is best to avoid oats.
• If you don't have a food processor to make the oat flour you can try using pre-ground oats or 100 per cent spelt flour, however, when I trialled these options the cookies turned out quite cakey, and I missed the interesting texture of the rolled oat flour.
• Baking soda: be sure to use baking soda here, not baking powder, as this will help give you the right texture. The molasses in the brown sugar will help activate the baking soda, which is why it's important not to swap the brown sugar for white sugar.
• Don't skip the chilling step: It is imperative that you chill the cookie dough for at least two hours before baking, as the dough is simply too wet to use straight away. Two hours is the minimum time required to chill the dough, overnight is preferable. Though previously I've left the dough for two days before baking, and the cookies were the best they've ever been.
• Bake one tray at a time: to ensure the cookies bake up nicely. When re-using baking trays, wipe the baking paper to remove any crumbs or chocolate, and carefully rinse the hot baking tray under cool water, before drying with a tea towel and returning the baking paper. You don't want to add the cookie dough onto a hot baking tray.