I have made three sheet cakes in three days.  They have all sunk.  I made two WASC cakes.  They failed.  Also sunk.  Made another one today With the the cake mix recipe on the back with an added box of pudding.  It sunk and is over done on the bottom.  I" recently baked a pund cake and it is perfect.  What in the world is going on?  I had to make this and freeze it.  I am leaving town and need to decorate when I get home.  My oven is o.k.  I am done after this cake.  Or I need to go to scratch.  Can Someone help me.  It sunk.  Then when I turned cake out of the pan it was also sunk on the botton.  I also used two flower nails. This was for a oging away cake for some friends.  I am going to have to call another friend I will not be able to bring a cake for the party.  I think I just need to quit doing this.  I have baked cakes for years as a hobby.  Always used Betty Crocker.  Made a 50th anniv. cake awhile ago and it was fine.  I just cannot do this anymore.  I have to give this up.  My frustration level is over the top.

I do all that you said, except I only have round Magic Line Pans.  But I have used my Wilton Sheet Cake pan for years and have not had this problem.  I am pretty certain my oven is o.k.  When I bake other cakes my oven has been fine.

Found on the net..

Some Reasons Why Cakes Sink or Fall In The Middle:

Cakes will sink or fall because:

1). Overbeating – too much air is incorporated into batter.

2). Underbaking - Oven temperature too low and/or too short a baking time.

3). Over or under measurement of liquid or under measurement of flour.

4). Using too small or large of a baking pan.

5). Moving or jarring cake before sufficiently baked or opening the oven door before cake sets.

Note: Only open oven door if absolutely needed, one-half to three-quarter's way through baking.

6). The most common error has to do with the oven temperature. Make sure you have an oven thermometer to test your oven for accuracy.

7). Depending on the recipe if you fold in egg whites, if not beaten fully or folded in too harshly, the cake could fall.

8). Even creaming the butter and sugar too much or too little can cause problems.

Do you think you are under baking?

Sometimes when cakes fall it's because of not enough protein structure. You can try reducing the sugar or use a higher gluten flour (I like king arthur all purpose). I am at 7000ft so I have to adjust every recipe that I try. Good Luck!

If you're sure your oven is accurate, you might want to take a look at your mix. BC has reduced the volume of the product by about 2 oz. I use DH but all the major brands have gone this route. I made a Devil's Food pound cake from the recipe on the side of the box (as I've done FOREVER with great results) and it failed miserably. Even though the mix is less, the rest of the ingredients i.e. liquid, pudding, eggs etc.  has stayed the same based on the old 18.25 oz. mix.  My cake shrunk away from the sides of the pan, shriveled on top and was about 1 inch high.  There was a thread on this topic but I can't seem to find it. CC members mentioned that, along with the reduced volume, BC has also changed the formula of it's product and it essentially sucks.

It was baked.. They bottom was really brown.  Should I just make the cake mix  as is on the back?  What do you all use?

remnant3333....is that AP flour for the extender recipe?

Thanks.  Have you tried this with the new cake mix size?

You keep saying your cakes sunk in the middle. Is it a smallish dip or a lg sink hole? Does this develop while baking or after it is taken out of the oven? 

This often is from using the wrong size pan for the amount of batter one has.  If you are making a 9x13x2 sheet pan you need:

1 cake mix (the new small size)

1 cup all -purpose flour

3 lg or 4 med eggs

1 cup sour cream

1 cup sugar (this can be reduced to 2/3 cup w/o problems)

1 cup liquid (can be milk, water, juice or whatever)

Mix all together as usual.  I always time my mixing for 2 minutes.  This is the perfect amount of batter for the 9x13.  I baked one this week and it turned out perfect in my 12x9x2 Magic Line pan.  I baked at 325 for abut 30 minutes (don't remember just now exactly).  (I have a new oven & it seems to be a bit on the cool side so I don't know if it is accurate.)  I do NOT use a flower nail nor wet/bake even stripes.

I finally got one to work.  Only a slight dip.  But get this.  I let it cool completely.  Went to level it and it was so moist that in the center it was so moist it dug it up.  I just patch it with scrap pieces. 

then turned it over on the cake board.  So the bottom is up.  i did not put filling in.  But how could
I ever torte this recipe?  Now  I have this issue to figure it out.  Any hints?

AIt really sounds underdone. The middle wasn't done.

ACould this be an issue with the new box size?

I agree w/leahs.  I have a feeling there is something wrong w/your oven.  It can "go off" quickly w/o one realizing it. 

It I cooked longer the bottom gets to dry.  This started after they changed the cake mixes.  I am seriously thinking of going all scratch.  I have a good white one.  Time consuming though.  I have a vanilla one I found I would like to try that has buttermilk in it.  Will have to try to to find a good chocolate.  I hate they changed the mixes.  I loved the french vanilla.  I coulod just use the cake mix with without the extenders.  Just wanted a little stronger cake in case I try a fondant cake sometime.  I only do buttercream.  People I knpow do not like fondant.  Would just like to learn to do one.

AThe bakery I worked for had a problem with the cake falling. A whole days ork scaling ingredients, mixing, scaling batter, baking ...and zoink.... They all fell. So we tried another batch and they fell as well. A bit of research revealed that it was a levening problem..... Too much levening! The baking powder was no good and when we replaced it with a new can they all came out good. I love using the recipe here in the recipe index at cakecentral.com called "Durable Cake for 3D and Wedding Cakes" and the link to the recipe is below. You can flavor it and modify it to just about anything you may want and it gets tons of compliments every time.

http://cakecentral.com/a/durable-cake-for-3d-and-wedding-cakes

:grin:

Although I'm no expert, it sounds to me like it's underdone - I think maybe your oven is the malfunction...I would go with what some of the other ladies said, and buy an oven thermometer. :) GL!

Chiming in again...Just for the record my oven is spot-on for temperature. I check it with an oven thermometer every time I bake. NEVER had any problems 'til the smaller mixes came out and the cake I mentioned in an earlier post DID have the texture & doneness of a cheap pre-packaged brownie. Will try adding the missing mix from another box but it gripes my a$$ to have to buy 2 mixes to get one!!!

Now about the Durable 3-D Wedding Cake...it calls for a DH mix. Are the instructions at the link for the 'old' size or 'new' size? I'd love to be able to use that recipe!

I use BC French Vanilla all the time.  I have tried to use the WASC recipes with the new size box, but I really don't like the texture OR the taste.   You can take 2 ounces from another mix and try to use that  to make up for the amount that has been reduced by BC.    But again, I don't care for the taste/texture so I have returned to just using the mix. 

I have done several cakes in 9 x 13 size but I don't torte...I just bake two cakes and layer them.  Yeah, it's a lot of cake, but it looks better IMO.    I also mix 2 recipes per pan so it is overfilled and I can level while still in the pan.  

Now, here is what I do to stop the 'not getting done in the center' thing.  (got the idea here on CC.)  Take an empty soup can...clean of course, open at both ends...grease it up with Crisco and flour and use that as your core.  I can't tell you how much this helps. 

After the cake has cooled I take out the core and level the cake while still in the pan (provided it has risen above the pan).   

So far, I've had pretty good luck with this method.  Yeah, it's a bigger core, but so what?  It gets covered.  HTH!