I did the last leek digging about four weeks ago and did the same as you, piglet6 - leek and potato soup, now frozen. But yesterday (lovely, sunny days here yesterday and today, by the way), I picked the last sprouts, had some for lunch today and made sprout and potato soup with the rest.
The only thing now left to eat on the allotment, other than the overwintered onions and garlic, is some curly kale which is looking fine. Shame about the purple sprouting broccoli which succumbed to the weather for the first time ever.
Oh, and we also picked the first rhubarb - lovely!
We had Leek and Potato Soup for lunch too. Sprouts and Parsnips with dinner. Yesterday had Prawn Cocktail on a bed of our own over-wintered salad. Still a few things to go at before new season kicks in. Regrettably Rhubarb only just showing.