Wow Julie - they look great! I have done one batch, and although they taste great, they don't look as good as yours.
The choc filling bubbled up and over the top of the tart cases a bit. I am not sure if I had the oven too hot (it was set at 220, but it is a new oven and I'm not familiar with it yet). But the pastry wasn't burnt. When I opened the oven door, the choc mix was really bubbling away. Maybe I didn't let the custard cool enough before filling the cases. It was lukewarm, but not stone cold.
What do you think I should do with the next batch? Cooler oven, cook for less time, or cool the custard more.