How can I fix my Russell Hobbs cooker?

How can I fix my Russell Hobbs cooker? I have a 2 hobs cooker.
My Russell Hobbs cooker is not working now,may be due to an electrical problem but I really don't know the reason why.On chrismas, while I was roasting a chicken, it suddenly did blow out. and then since then, it does not work at all.I thought that there might be or was a faulty mains supply socket and then, I plugged it into another socket but it did blow again out.I really do not know what went wrong.I called a repairer on the phone, they said the servicing fee is £65.00 without parts purchase but included VAT.

Here is cooker reference:

Russell Hobbs
Model No. 9942-10
230/240V~,50H2
Model No.9942-10 0902 1408
Pro Nr: L1120GB02

As I am claiming Job seeker's Allowance, I see that it an exhorbitant price.I will not afford it.May you please send some information which can help me? May you please tell mewhich parts I need to buy in order to get it fixed?May I have some instructions?I am 39 years old and did Electronics at College. I think that if I have everything on hand I am confident that I can do fix it.

I shall be very grateful to you if you can advise me

Kind Regards,

Sebastien M KINKANI