In a dry pan, add the coriander, black peppercorns, cumin, fennel, and caraway. Toast the spices until they start to darken and are fragrant. Remove to a mortar and pestle and grind to a uniform powder.
In a large mixing bowl, add the lamb, toasted spices, remaining spices and all other ingredients. Mix by hand, working fairly aggressively. You'll work this mix more than you would a traditional meatball, but not to the point of mush. Ingredients should all be evenly incorporated.
Divide the mixture into even thirds (or smaller if using smaller skewers). Take one of the portions, form it into a ball, and stick the tip of the skewer into it. Squeeze the meat down the skewer evenly, forming a long, uniform tube-like shape. Uniformity is important for even cooking.
Grill the lamb over direct heat and serve warm with tzatziki sauce, sumac onions, felafel, grilled vegetables, hummus, olives - any or all of your favorites!