Start by greasing your tin. I used a Bundt tin, but any tin, dish or bowl will do. Rub the inside with butter - ensure to do the corners or the central piece if using a Bundt.

Get everything ready - put the sweets in a bowl, chop the chocolate bar if necessary and put them near your tin. Decant the popcorn and place it near your cooker. Have the butter handy near the cooker too.

Put all the marshmallows in a very large pan. Turn the heat to medium and using a silicon spoon or spatula, stir the marshmallows around the pan. When they start to melt a bit, add the butter and continue stirring. Keep stirring! It will eventually all join together and be a big (it will grow) pan of white fluff!

As soon you have a cohesive white fluff, turn the heat off and quickly stir in a handful of popcorn. Keep adding handfuls and mixing in. Use the silicon spatula!

Depending on your tin, either put some sweets at the bottom or around the edge (it's okay if they fall down). Using the spatula, spoon half of the mallow coated popcorn into your tin. At this point you can re-arrange (or add) the sweets around the edge if needed. Gently press the mixture into the tin then equally distribute your chocolate bar, keeping away from the edges (it's a surprise)! Using the silicon spoon, add the remining popcorn mixture and press into the tin until it is equally spread out and level. Press it down firmly. If you want to you can squeeze a few more sweets around the edges.

Place in the fridge to chill, while you wash the saucepan and tidy up

Remove the tin from the fridge and see if you can move the cake at all. A flat spatula is useful to ease it away from the edges (and centre for the Bundt). When it looks loosened, turn the tin upside down and gently tap the base until the cake comes out. Place on a plate (stick the sweets in if needed) and return to the fridge to cool further.

Wash your tin up (it will be greasy).

Break your chocolate pieces up, place in a small bowl and microwave in short bursts until melted (this should take a maximum of 90 seconds in total).

Get your cake out again and place on something which can get chocolatey! I used a wire rack over the worktop, but you can use a plate, a chopping board or the worktop. Using the tines of the fork (the prongs), dip it in the melted chocolate, then drizzle it backwards and forwards across your cake. Repeat until you're happy with it! Pop your cake on a plate and pop back in the fridge to chill. Eat what's left in the chocolate bowl (yes)!

When you're ready to serve the cake, remove from the fridge and allow to soften for a few minutes. Use a good strong knife to cut slices.

Enjoy!