I have been meaning to make this cake forever! I finally decided to give it a whirl today.. unfortunately i had only half the amount of light brown sugar so i used half light and half dark brown sugar to make the caramel. I dont know if thats what the problem was but it was a hot curdled mess. at first i thought it was supposed to be that way but then i checked online and i can see everyone had a real smooth caramel to add to the cake! I used my thermapen it was taking forever to reach 114 and even then towards the end i realized the edges were at 116 degrees C and the middle ws at 111 C so i took it off , but before that itself it was a curdled mess… I also measured everything . The only thing i could think of was
A - my milk was cold but i dont think this could be it cause it was all heated togethr and boiled anyway?
B - my pan scorched the sides?
C - was it the drk brown sugar?

So i ended up throw all that away cause i dint want to risk wasting more butter and flour! and clearly my caramel ws not upto par , just want to figure this out before i try again! Its for a birthday girl so really dont want to screw it up! Some one anyone help =)

It was most likely the dark brown sugar.  Milk heated with acid will curdle every time, and because molasses is acidic, dark brown sugar is more acidic than light brown sugar.  A second thing to check is the date on your milk- as milk approaches its use by date, it gradually becomes more acidic as part of the aging process. 

Use the freshest milk you can find, and use light brown sugar. 

If there is just a tiny amount of curdling, I would go ahead and make the cake as the eggs, flour, etc. will bind the separating parts of the caramel together.

Hey Julie, just reporting back with my results.
I redid the caramel, the same thing happened again ! it jst split on me even after bringing it to the required temp. So i just blitzed it in the blender at which point it was smooth well almost smooth i could say and then i AGAIN brought it up to temp. at this point it was very very thick, like run our hands thru the back of a spoon and the mark will stay kind of thicK. From the pics online im gathering thats not right either…Anyhoo i proceeded to make the cake It had the msot wonderful flavour but it was dry. I dont know if this was because of the viscosity of the caramel or because i overbaked it somehow. Please help me figure this one, i loved the flavour of the cake but it was so dry it was liek stale bread!!! i
I was just htinking if i blended the mixture together and then boiled it to soft ball would it work?

I don’t see any reason to bring the caramlized syrup up to temperature a second time, it strikes me that that might result in too much evaporation of water and help create a dry cake.  Not saying that it’s the only reason your cake was dry, but it could be a contributing factor. 

If you suspect even a little bit of overbaking, it can be helpful to take the internal temp of the cake as you remove it from the oven, then you’ll know if that was the case.

Perhaps others who have made this cake will chime in with more ideas on the curdling problem!

Hey Julie. In hindsight I think why did I do that anyway ? I think it had to do with the fact that my caramel was more brown sludgy water And floating curds rather than caramel caramel so when I blitzed it and got a cohesive mixture I decided to bring it to soft ball again I case their strike it hadn’t actually come to that stage. nywY I also forgot to mention that ere was a considerable dip in the center. Like crater deep ! Now I made the caramel a second time and this time I around I blitzed the entire mix first before I brought it to soft ball stage in order to make sure I lessen the chance of splitting, it worked I got very slight graininess but really nothing compare to my earlier disaster. I proceeded to make the cake. Just took it out in fact. The crater is huge ! , like non salvageable. I got a really high cake all around a crater Lmost touching the bottom !! It’s really soft though. I’m using swans down and rumored baking powder. Please Someone help me out this cake is perplexing !!

A few things to check:

-When making the caramel are you using only 3/4 cup of the milk, reserving the rest to add after the caramel is made?

-Did you use regular whole milk and light brown sugar, plus regular butter to make the caramel?

-Did you measure and have 1c of liquid caramel after it came to 238F?

-Perhaps check your thermometer by testing the temp in boiling water.

-Is underbaking a possibility (did you happen to take the internal temp)?

-Is your oven running cool?

I add 3/4 cup of milk not 3/4 of the entire amount. So zi have 1/2 cup left to add to the caramel once it’s done. And yes I always have a cp of caramel ! This is just baffling to me! Nope to under baked cause I checked internal temp ! And no oven is fine I bake every other cake in this oven with no I’ll effects ! The only thing I can think of for the sinking crater is the baking powder? I used rumford I usually use foster Clark’s.cosuld that be it ?

I’ve used Rumford baking powder extensively with Rose’s recipes and haven’t had any problems with it, so I wouldn’t think that’s it.  I’m stumped! :(

I’ll see if I can get Woody to take a look at this thread, but in the meantime, if anyone else has any ideas, please chime in!