Asparagus tart with walnuts and parmesan

I blame Delancey for planting the seed that sprouted this tart. On one of our regular visits, I ordered a dish consisting of asparagus that was perfectly charred in their wood-burning oven, walnut cream, and slender shavings of parmesan. It was a rare moment in which I was cursing the fact that my children eat their vegetables; I wanted them to leave their asparagus for me. Anyway, with the addition of a simply dressed salad, this tart makes for a perfect summer lunch.