Sourdough loaf = failure!
Can someone please help? I bet you have heard this a thousand times but here goes:
I recently purchased a sourdough starter via Ebay, I activated it with equal parts flour and water and after a couple of days it appeared to be working. I continued this for 5 days and then set about preparing my first loaf. I followed a proper recipe and all went well, first prove took some time but produced a good rise. Once I had knocked the dough back I placed the dough in a floured cloth inside a mixing bowl and covered with cling film. I left the dough overnight. The next morning the dough had risen above the top of the mixing bowl, " jobs a good un" or so I thought. I heated the oven to 220c including a metal baking tray, when the temp was reached I carefully tipped the risen dough out of the bowl. To my horror the dough collapsed like a deflated balloon, not deterred I decided to bake it anyway in the hope that the loaf would rise, it didn't and came out looking like a cap mushroom without a stalk!!
So what went wrong, this was my third attempt at this sourdough lark and as you can imagine I am getting pretty peed off. Can anyone tell me what went wrong??