what causes a cake to sink in the middle? For the last 6 months, any loaf type cake has been sinking in the middle.

Glad to - hope it does help!

Okay, I will follow your advice. I think the problem could be the cooking time and lack of creaming enough. Thanks for your help!!!

When I'm creaming butter and sugar I actually walk away from the mixer to let it get really, really pale. You're whipping in lots of tiny air pockets. Also, don't be afraid to bake it to a good, deep golden brown. Lots of flavor permeates the cake when you caramelize those sugars. I love your persistence!

Maybe I'm pulling out too soon??? I'm afraid of a dry cake so I always start checking early in the time. As soon as I see it pulling away I'm taking it out. It seems cooked in the middle when a tester comes out and the cake tastes ok. Maybe I'm not creaming long enough? In a KitchenAid stand mixer would you say a couple minutes is enough?

I'm doing all the steps exactly as the recipe calls. I warm up the eggs but I usually just crack over the bowl...maybe I should add them more easily.

Hmmmm. Well, so much for that idea. So now let me ask how you're mixing. Are you starting with room temp butter and eggs (for the latter, soak in a bowl of warm water for 5 min.)? Are you creaming the butter and sugar until pale and almost white? Do you then stop the mixer and scrape all around the sides and bottom of the bowl? Are you cracking your eggs into a measuring cup so as to easily add them one at a time with the mixer on low speed, letting each be FULLY incorporated before adding the next? Are you sifting your dry ingredients together onto a sheet of parchment, and adding about a third of them along with half your liquid (to which you added the vanilla, right?), which in your case is the ricotta, right? Do you mix just until the dry stuff is moistened, then repeat again with another third of dry and the remaining liquid? Do you add the last third of dry, let it mix, then scrape your bowl again all the way around the sides and bottom, then mix in what you scraped loose? Ok, just asking. And do try setting your temp a little high. Another thing that's important is to bake it until it's completely done - when you can tap a finger on the top center and it feels springy, not squishy.

I live in Fort Worth, Texas, so elevation should not be a problem. I have an oven thermometer so I know the temp of the oven is accurate. It has only happened in the last 6 months...never had this problem before. I bought brand new baking powder and baking soda so those are fine. Thanks for your insight.

Where do you live? In other words, what is your elevation? If you live above 2500' you'll benefit from increasing your proteins (flour and egg), decreasing your baking powder, and increasing the baking temp 25 degrees as HLA suggests above. If you can tell me your elevation, I'll give you the adjustments to each. A sunken cake is so sad. It's always a pleasure when someone smiles at her cake.

My suspicion is the egg proteins and starch granules are not setting up fast enough in the center. You may need to bump up your temperature by 25º or consider decreasing the amount of sugar (less sugar will decrease the temperature at which the protein and starch will "set.") Perhaps betteirene or boulangere or one of our other experienced baker's will have some other suggestions.