The last time I dined on sweetbreads at a restaurant, the meal was colored by an incident that I'm not proud to tell you about, but I may as well given the moral of the story. We had only begun eating the sweetbreads and other dishes brought to the table when my friend used his fork to pick his way around the clumps of perfectly crisped, creamy sweetbreads.
"Look at all this membrane the kitchen didn't take off," he said, furrowing his eyebrows.
I peered more closely at the dish and spied a very small, yet discernible sheath on the exterior of a piece of sweetbread.
"How deceptive," he said with a grimace. "You order something thinking that the kitchen's going to take care of the prep work, and instead you get a pile of organs that's barely been cleaned up!"
"Deceptive? Deceptive? You think a little membrane left on a piece of thymus gland is deceptive?" I said.
"I'll tell you what's deceptive. Multinational corporations wielding insidious channels of power. Political candidates funded by interest groups that have their hands in every honey pot in this country. That's deception, and you're complaining about the membrane on a sweetbread?"
My friend gave me that horrified look of pity you reserve for people clearly off their rockers.
Then I got off my soap box (er, rocker, maybe) and proceeded to eat his dish of sweetbreads, because it's really lonely and not very fun being up on a high horse.
Sweetbreads, though mild in flavor, have an offal-reminiscent flavor somewhat akin to brain. People often describe the texture as "tender" and "creamy"; I would add "marginally juicy."
Sweetbreads made from an animal's pancreas and thymus glands (called the "heart sweetbread" and "throat sweetbread," respectively). Heart sweetbreads are usually slightly larger, but they taste the same and are cooked the same way. They get crispy on the outside and stay soft inside, while the interior is almost ripe, bursting with meat juice.
Make sure you remove the membrane from the organ when you bring home your pound(s) of sweetbreads. To do this, simmer the sweetbreads so they firm up and are barely cooked through. Then, with your fingers and a sharp knife, peel away the membrane, the gristle, the tubes, and other animal-like bits you'll find in the glands.
For whatever reason, the process of removing the membrane from sweetbreads is off-putting and intimidating to home cooks, but fear not. The section of the sweetbreads are held together by this network of membrane and tissue, and the idea is to peel away as much as you can while still keeping the organ in sizable clumps. It's not that difficult. You may end up with smaller bits of sweetbread, but even those marble-sized nubs will stay tender when crisped up in the pan.
Besides its amazing flavor and texture, sweetbread is nearly impossible to overcook. Unlike a slab of liver, you can sear the exterior of sweetbread to your heart's content, without worrying about the interior turning chewy and tough. Your cooking timeframe, in other words, is extremely forgiving and long—minutes long, rather than tens of seconds.
The only real concern? What flavors to pair with this dish of crispy, tender thymus and pancreas glands. Keep it simple: something sour, like lemon or capers, with good salt and freshly ground black pepper. The acidic component will be a nice foil for the richness of the glands. Serve with fresh vegetables, preferably those that are creamy and nub-like too, like fava beans and peas.