What is "baking aluminum"?

Question

I want to make a medieval recipe for a medieval-themed party, but it calls for baking aluminum. Is that...alum? Some kind of baking powder? Something else entirely?

OK, the baking aluminum was measured in teaspoons. So I doubt it's a teaspoon of aluminum foil.

Answer 1

from what I can find on the net this is the closest thing I can find (Sodium aluminum sulfate (alum) baking powders) hope this helps

Answer 2

It's just aluminum foil. It comes in a box on a roll. Ya know, just the simple aluminum foil. I think they call it baking foil because you can put it over your food and throw it in the oven to bake.