Thought I'd give it another go, this time using Ricki Carrol's 30 minute recipe. I added the citric, brought it to 90, let it set and added the rennet. Wandered away for a few minutes as it said leave it to sit 3-5. It should have curds by then. But it doesn't. It's been seven minutes and while it's thicker, it would appear to be cream rather than curds. I don't think miss muffet would approve. So...as I'm sitting here looking at my cream, what did I do wrong? And...how to fix it?