Is a toaster a conduction convention center or radiation fastest do tomorrow

It should be radiation.
Radiation is a flow of electromagnetic waves, and the toaster net emits radiation, by the coils in the toaster. At this point, the toast net absorbs radiation, and therefore gain heat.
Note that everything absorbs and emits heat all the time, but if the thing is colder than the environment, it's a net absorber. If hotter, it's a net emitter.