A few words on lardo and bone marrow (you can skip this if you're one of those sophisticated food person types): Lardo is an old Roman specialty that shows up on charcuterie plates a lot these days. It's literally just pig fat that's been cured with spices (like rosemary), and it comes sliced but has a buttery consistency you'd expect from pure fat. Bone marrow is also quite fatty but is not fat, technically, but blood-cell-producing tissue. It was popularized as a bistro-y thing you'd dig out with a knife and spread on toast when it appeared on the menu at Blue Ribbon Brasserie in SoHo in the mid-1990s. It's rich, creamy, and primal. If you're out drinking, it can be a more sophisticated answer to late-night french fries.
Bone Marrow Pizza Is In
I guess it was inevitable: After lardo pizza became ubiquitous, thanks to its inclusion on almost every Mario Batali menu, bone marrow pizza would follow. So far, bone marrow (extracted from the bones, duh) has been spotted as a pizza topping at Boston's Coppa Enoteca and San Francisco's Flour + Water. Both are paired with freshly grated horseradish. So what does it taste like? I've tried the Flour + Water one, and it was tasty, although truth be told, you can't tell you're eating bone marrow per se, because it melts down into a pool of really rich grease that mixes with the cheese.