A little concerned you say it has only 2 cables - it should have an earth, live and neutral..... How old is the oven and has anyone owned it before you?
On the back of the oven should be a termination cover plate - take this off and you will likely see 3 termination points for an earth, live and neutral. If this is the case replace the cable already attached with a new length of 6mm twin and earth and make the connection to the connection plate behind the oven or to the control unit above your work top if there is no low level connection plate. If you need 6mm cable let me know, i have some left from updating my kitchen.
If you do this ensure the cooker circuit is isolated. If you dont know how to do this and prove to yourself its dead get someone in who does. (and make sure you know your live from your neutral.
I would offer but your not on the doorstep!
