It's up to the employer to decide if your certification and job skills are worth the extra time, effort, and expense to hire you vs someone else who will not require a visa. I have never tried to work in an Icelandic bakery so I can't offer you any personal experience.
Also, once the employer has decided to hire you, they submit the paperwork to the work directorate who will also decide whether or not to approve your application.
I suggest you try visiting Iceland and talking to potential employers if you can. Icelandic jobs are very often found through personal networking, and less so via advertisements.