4get, simply not cooked for long enough, when you test the cake, if you're not sure, then another 5 mins longer cooking time won't hurt, but if you take them out 5 mins too early, then they will sink, so err on the side3 of caution!........
Ok 4get, turn the oven down about 10 or 15 degrees, and cook for longer, but slower, should work, they are cooking too fast on the outside, and not cooking on the inside..............or lower the oven shelf and still cook longer......trial and error!.....You'll get there!.......
LOL well between us we're either too wet, too dry, too hot or can't mix it. Crap oven is probably the main reason!
thanks classylady and welsh for your answers.