Hello Friends: I've never baked a full commercial-sized sheet cake before, any advise? Do I line it with parchment paper? What recipe should I use and can I use boxed mixes at all, or stick with a scratch recipe? I recently bought an unfrosted cake from a Bakery instead of making my own 1/2 sheet cake, because I was terrified of baking a full sheet cake. Thanks in advance for any help.
I doubt if a full sheet will fin in a home oven, assuming that is what you are using. You can bake 2 half sheets and put them together.
just like any cake -- only bigger
and only as big as will fit in your oven
which means for me -- two 1/2 sheet cakes that I then put side by side to make a full size one.
as for recipe -- your favorite
I being of the enhanced & extended WASC (tho' I modify even that to make one half using all butter recipe DH and the other butter recipe DH chocolate -- white cake? ICK!)
I do do the flour nail heat core trick along with using bake even strips and baking at 325 degrees.
and when they come out of the oven having been backed until done -- done being measured by smell, sight, and poke and toothpick (forget the clock!) -- I remove the flower nails (requires flipping over and pulling out with fork -- too hot to do by hand!) and then back into pan long enough to use large cooking board to press down any dome and flatten the cake (much better than trimming as gives a denser cake!)
then out again to finish cooling unless I'm going to freeze them then it's wrap in plastic and foil.
when ready to deco --
onto a VERY sturdy base (very important!! -- I use 3 to 4x 1/4" layers of foam core glued together and covered.) put two cakes side by side with a bead of icing in between at joint sometimes and other times not.
then ice the monster -- the icing tip is a time saver!
nothing to be scared of.
just be sure to measure your oven to see what is the largest pan that will fit and still allow for air circulation all the way around.
Are you sure a full-sheet will fit in your oven? It's 24"x18". Most home ovens cannot accomodate that size. Some cannot even accomodate a half sheet (18"x12").
I have made my first two 1/2 sheet cakes this past month....I can not explain how badly you need to put parchment paper in the bottom of the pan...the first one I didn't and when I flipped it was not pretty.....the second one I did the parchment paper and it came out beautifully!!!