According to Webster:
Main Entry: 2cook
Function: verb
Date: 14th century
intransitive verb
1 : to prepare food for eating especially by means of heat <French cooking>
2 : to undergo the action of being cooked <the rice is cooking now>
3 : occur , happen <find out what was cooking in the committee>
4 : to perform, do, or proceed well <the jazz quartet was cooking along> <the party cooked right through the night>
transitive verb
1 : concoct , fabricate —usually used with up<cooked up a scheme>
2 : to prepare for eating by a heating process
3 : falsify , doctor <cooked the books with phony spending cuts and accounting gimmickry — Colleen O'Connor>
4 : to subject to the action of heat or fire
— cook·able \ˈku̇-kə-bəl\ adjective
— cook one's goose : to make one's failure or ruin certain
So i guess microwaves and toaster ovens count.