Dig;
To answer your question as to what to put on the bottom of the pan to prevent the crust from sticking, you should season any bright aluminum pan before using it. This is done by setting your oven temperature at 425F, then brushing the pan, inside and out, with salad oil, place the pan in the oven to bake for about 20-minutes. Be sure to place a piece of foil below the pan to catch any oil that might drip off, and be prepared to handle the smoke created by the seasoning process. I like to do this at least twice, the pan should now have a light gold tint to it which will continue to darken to almost black with continued use. DO NOT allow a seasoned pan to soak in water, to do so will make the seasoning peel off like a bad sunburn, you will then need to strip all of the seasoning off of the pan and start all over again. Remember the admonishment about the cast iron skillet? Never wash it! Just wipe it out. This should also apply to a seasoned pizza pan. The darker it gets, the better it bakes. One other thing, you will always need to put just a very thin coating of oil in the pan to allow the baked crust to release properly.
I'm betting the cracker like crust you made was baked in the bright pan. The bright surface reflected heat away from the pizza so you had to bake it longer to get color on the crust, this resulted in extreme drying of the crust, hence the cracker like characteristics.
Tom Lehmann/The Dough Doctor