Prepare an 8x8 inch square tin with non-stick baking paper.

Measure out your cornflakes and crush them a little. Don't crush them all super fine, mix it up for a bit of texture. I actually did this with my hands!

Place your marshmallows and butter into a large saucepan and allow to melt on a low heat. Keep stirring so it doesn't stick to the bottom of your pan.

Once smooth and very sticky remove from the heat and add your cornflakes to the pan. Mix them so all the flakes are coated.

Then place your mixture into your tin. Press it down as tightly as you can, it's very sticky but I find it becomes less and less sticky so keep pushing it in. You can use your hands or the back of a spoon works well too.

Place all your caramel ingredients into a saucepan on a low/medium heat. Allow the butter to melt and the sugar to dissolve. Mix well to ensure it doesn't stick to the bottom and is combined.

Once the sugar has dissolved and the butter melted, turn the heat up so the mixture starts to bubble a little. Keep stirring continuously for about 5 minutes (although I often going to about 7/8 minutes), the mixture should have thickened and also developed into a darker golden colour.

Pour on top of your cornflake layer, spreading it so that it's even. Place in the fridge to set I tend to leave it for no less than 90 minutes.

In separate bowls melt your milk chocolate and your white chocolate. You can do this in the microwave, or in a bowl over a saucepan of boiling water on the hob. If you melt it in the microwave, make sure you mix it every 20 seconds or so to ensure the chocolate doesn't burn.

Pour your milk chocolate all over the top of the set caramel layer. Make sure it spreads evenly to the edges.

Spoon on blobs of your white chocolate and using a skewer or a knife, swirl the chocolate around to make some random patterns!

Place back in the fridge to allow the chocolate to fully set. This often takes a couple of hours.

Once fully set, remove the millionaires from the tin and slice into squares. To help the chocolate top not to crack - remove the millionaires from the fridge about 30 minutes before you want to cut it. Also I find that warming your knife on hot water before each cut, helps the knife to slide through the chocolate. Enjoy!