Ideally for both inside and out. But if no food-safe options are available I might consider doing the inside differently than the outside.
Also, ideally, commercial glaze, but again if no other options I might consider a recipe.
But at this point, all options are on the table if the result is good enough.
I guess this brings up the question of what would I consider good enough. I have tried Amaco, Mayco, Georgies, and Cyote black glazes. The Mayco Satin black SW-140 is probably the closest to what I am trying to achieve. I have seen a glaze by Spectrum (253 Satin Black) which looks pretty good too but have not tried it yet.
I am curious if anyone has found a glaze or process (that they are willing to share) that really stood out in this regard.