Leek and black pudding tart

When I was working in a chalet many years ago, I asked a friend to pick up some chorizo or spicy sausage for me on her way back from her aperitif(s)! She did not speak French and brought back a boudin noir, a French version of black pudding. Running late, and with guests hungry after a day’s skiing, I used the boudin noir in my chorizo tart recipe and it was magnificent. It is now one of my all-time favourites. You can, of course, use chorizo if you prefer, but I think this is much better.<