Just had black pudding and... um, what is it? My friend's being all mysterious and laughing.

So, you've just had black pudding for the first time and your thoughts are a swirl of intrigued confusion mixed with a dash of betrayal from your friend who seems to be hiding something behind that mischievous grin. You're not alone—many people outside of where black pudding is a staple find themselves bewildered upon their first encounter with this unique dish. But worry not, you’re about to unravel the mystery of this traditional delicacy.

Black pudding, often known as blood sausage in various parts of the world, is a type of sausage that is generally made from animal blood (usually pig's blood), fat, and a filler like oats or barley. The combination is stuffed into a casing and then cooked. It's a staple in British and Irish breakfasts, but its origins stretch far and wide, all the way to Europe and Asia, where each culture has its own twist on the recipe.

Still with us? Great! Let's break that down a bit more:

1. Composition: At its core, black pudding is made of blood. Yes, blood. That key ingredient is what gives it the distinct dark color. It’s combined with fat, which can be from pork or beef, providing the pudding with its richness and moisture.

2. Filler: To give texture and substance, fillers like oatmeal, barley, or breadcrumbs are added. This bulks up the sausage and also helps in absorbing and maintaining the flavors in the pudding.

3. Seasoning: A variety of herbs, spices, and sometimes onions are used to season black pudding. This mix can include marjoram, mint, thyme, and allspice, among others. The combination can vary widely from one recipe to another, which means no two black puddings are exactly the same.

4. Cooking: After stuffing the mixture into casings, the sausages are cooked, which can be done through boiling, grilling, frying, or baking. The final product can be eaten straight away, or stored and reheated for later consumption.

Now you know what black pudding is, but here's some further food for thought.

In culinary history, black pudding is one of the oldest forms of processed food, with versions existing in ancient times. It's not just a full English breakfast component; countries like Spain, France, and Sweden have their own versions, too.

Nutrition-wise, there's much to discuss. While it's rich in protein and iron due to the blood, it's also fairly high in fat and cholesterol. As with any food, moderation is key.

As you explore the wide world of unfamiliar foods, remember that dishes like black pudding come with a cultural and historical backdrop that enriches the experience. So next time your friend serves up a curious culinary delight, dive in with both an appetite and an open mind. Who knows, mysteries like these could turn into your next favorite food adventure!