It always comes as a surprise to me when people visiting from the U.S. don't know what eating 'a' couscous involves. Sure, now nearly everybody knows what couscous is — the so-called "grain" I mean. People tell me they eat it as a breakfast cereal. But around the Mediterranean — Morocco, Algeria, Tunisia, France, etc. — a couscous is big bowl of tomato-based, spicy broth full of vegetables and meats that happens to be served with the couscous grain — a.k.a. semoule or semolina —along with meats and sausages.
I believe current polling shows that couscous has replaced more traditional French dishes like blanquette de veau or bœuf bourguignon as the favorite meal of most French people. Couscous is satisfying in winter because the broth is hot and the vegetables and meats are comforting. And couscous is delicious in summer because the broth is spicy and light, and because the meats served with it can be grilled over a fire.
Traditional couscous includes lamb in one form or another — spit-roasted lamb that's called méchouis, or lamb stewed in a sauce or right in the couscous broth. The lamb-and-beef sausages called merguez, often grilled, are served alongside. Other meats, including meatballs and chicken, are good too. You can make a couscous with rabbit or turkey, veal or mutton.
The vegetables are tomatoes, carrots, onions, turnips, green beans, zucchini, eggplant — either summer or winter vegetables. The most important thing is to have a spicy, herby broth to cook them in.
And finally, there are the garnishes. Chickpeas are pretty much required, and they are cooked and served separately (though you can also put them right into the broth). Plumped-up raisins lend a note of sweetness to complement the spiciness of the broth and meats. And then when it comes to spiciness, there's nothing to compare to the red-pepper paste called harissa that is inevitably served alongside couscous and broth.
Serve yourself "a mountain" of couscous grain in a shallow bowl. Dip into the broth to get some vegetables and meat and put everything over or around "the mountain." Then use a ladle to get a good serving of the couscous broth. Put a spoonful of harissa paste into the ladle of broth, stir it well, and dribble the mixture over the grain, vegetables, and meats. Don't forget the chickpeas and raisins. You won't need bread. Be careful — it's filling.