Rigatoni with Mushrooms I'd Never Heard Of

Last week, as you may have noticed on my visual market post-mortem, I came home with a pile of cool-looking maitake mushrooms from the farmer's market. I probably sound like I know what I'm talking about, but in truth, I had never heard of maitakes before I spied them on a vendor's table next to the Lion's Manes (another new-to-me variety) seven days ag…