Food

Does anyone have any experience of using a hay box*? I'm tempted to make one as I have plenty of polystyrene to use for insulation, and plenty of ply for the box. I'd be interested to hear any first hand experiences.

*Basically a well insulated box that you put a hot casserole dish into and leave overnight to cook from the residual heat, saving fuel as you're not constantly heating the dish in oven/on the hob.
In case anyone else is interested... I made myself one if these. Knocked up a box out of some thin ply I had in the garage and used polystyrene slab for the insulation. Cost me nothing other than a little time and a couple of nails.

Cassoulet went into the pot the other night, brought to the boil and popped it into the hay box. Then went to bed... 8 hours later and the contents were at about 45 degrees. So back on the hob for another 15 mins it goes and then back in the box.
... work ...
Come home to find cassoulet is still at about 50 degrees. Perfect! So knocked up some veg to go with it and filled my face :)

Normally this would have had about 30-45 mins on the hob and then 3ish hours in the oven so it saves a lot of fuel as this only had time on the hob.