After spending some time with making a 3d model,
I then tried to order in in alumide from Shapeways or Materialise. Both companies found it hard to print.
Shapeways
As I was printing on the edge of alumide specification at 1.5mm wire thickness, there were some defects.
Burn Test
I finally got a model of the master shape in my hands and set about making a simple cross shape to "burn" in to the toast. Set the pixel to a cross pattern.
The adding to the toaster.
The bread held up longer then the model. Although the model was closer to the heat.
One the other-side the bread was nicely toasted, but no pixels. Fail