Total caketastrophy!

My latest attempt to make an Earl Grey tea loaf was a total caketastrophy - I've never had such a cake disaster! All was going well, the mixture tasted lovely when I licked the spoon, but when I went to take it out of the oven all hell broke loose. It had collapsed in the middle, like a volcano. I can only assume it developed a huge air pocket in the middle which exploded. I nearly cried. But the bits around the side still tasted pretty good. Note to self: knock the air out of the tin before you bake!