Preheat your oven to 160C Fan / 180C and prepare a baking tray with non-stick baking paper.

Place your peanut butter, egg and brown sugar into a bowl and mix together until smooth - I use an electric hand mixer.

Once mixed, add in your M&Ms and stir them in with a spatula. Make sure you leave quite a few to one side to push into the top of each cookie - don't forget!

Your dough should be ready to roll into balls now - it's soft but shouldn't be too sticky to roll. However, peanut butters can vary so if it feels too soft, just pop in the fridge or freezer to chill briefly, like you would often do with cookie dough. About 30 minutes should make all the difference if needed.

Roll your dough into balls - mine are around 50g each. Place your balls on the prepared tray. My tray is large and I put 6 on each tray, they spread so you don't want to put them too close together.

Either with your fingers or a fork, press the balls down slightly and push a few extra M&Ms in the top of each.

Place in the oven for 10-12 minutes, until cookie shaped!

Allow to fully cool before moving the cookies. Enjoy!