basically this is a box that heats up in the inside of it & thussly cooks your food.
probibly only usefull for traviling magi that like to cook/bake,but could be useful for staing warm on a cold nite(maybe?) 
tell me what you think of this item!
I think there is something like this in Covenants? or 4th ed Grimore? Serfs parma so I don't know what the level would work out to be, but it shouldn't be huge.
Could actually be more generally useful than you suggest, Abe. An oven for the covenant that is reliable and required no fuel. Probably save the need for at least 1 servant. Depending on the size of the oven it could be more.
Also, reliable and soot free cooking should help contribute to improved living standards (health modifier) though not enough on its own.
Also, could a ring duration achieve the desired goal instead of an enchanted item.
I was meaning to ask, what happens to ring effects inscribed on portable objects? Does it still work? If so then that could get very cheap for specialists.
Huh. Was only meant to be tuppence worth. Oh well 
We gotta install magical ovens
Custom kitchen deliveries
(...)
Magic for nothin
And chicks for free
lolololololololol
on a different note,the oven could(for portabiblities sake)be the size of today's easy-bake oven.
But can only be used by characters with either Small Frame or Dwarf Flaw.
the idea for the size was a for example only.
This oven is indeed stated in the Covenants supplement, along with various other nice ideas.
It adds flavour, but would not be the thing my magus spends seasons on, if I can just hire more staff.
The Luddites of the world bow down and pay you homage!
this item MIGHT be usefull for labwork as well(maybe?)
What would be REALLY useful would be...
A bus, MAGIC bus! 
*wanders off whistling other classic 60's tunes
Actually, this kind of item is one of those nice items that can be made with circle/ring spells. Since you only need 1 per covenant, roll 100 times in a season (spont it) and have a handy unravell the fabric of Ignem spell available to cope with mistakes. You are bound to spont the level of the spell in a certain moment. Do it under relaxed circumstances to avoid those pesky botches, though! 
If you need several of them, invent the spell/item. But for a single items in the covenant that do not require massive levels, circle/ring sponts work wonders to improve your living conditions.
Cheers,
Xavi
what other effect besides cooking would you fine people use this oven for?
I'd push witches into it.
Have to be verrrrrrrrrrrrrrry teeny tiny witches! 
And newts. You can place newts there as well.
Xavi
Newts are so much nicer than witches though. Poor newts 
what sort of recipies do you think that magi might be found of?
Hmmm Well Flambeau Magi would likely prefer something hot and spicey, Jerbiton's would likely prefer something sweet but whatever you do, never try to serve Humble Pie to a Verditius!
Why don't you hire a chef with a high profession cook score? They will make sure you magi are well fed. Perhaps a few kitchen maids and if really needed you equip one of them with wet sellery and an egg whisk. 
Power to the ludites!
Hmmm sounds kinky! 