In the fall, use greening or wine sap apples. In the summer, try fresh apricots, or the type of hard, fuzzy, green crab apples called, in Morocco, lehmenn. In winter, I recommend the heavy and rich tagines made with prunes or dates, and, anytime of the year, lemon and olives.
The combination of lemon and olives is so popular in Morocco that one ought to regard it as a general theme on which variations, each one applicable to a specific category of sauce, are possible. Different-flavored olives work best with specific combinations of spices. For example, the following multi- spiced classic employs the green-cracked type of olives, more appropriate here than mellow reddish purple olives, which are used with sauces made with a combination of ginger, saffron, and olive oil. In the following recipe, as the sauce begins to boil, the cracked olives will release some of their juices, which in turn will thicken the sauce.
Most tagines involve slow simmering of less-expensive meats. The ideal cuts of lamb are the neck, shoulder or shank cooked until it is falling off the bone. Very few Moroccan tagines require initial browning; if there is to be browning it is invariably done after the lamb has been simmered and the flesh has become butter-tender and very moist. In order to accomplish this, the cooking liquid must contain some fat. Don't be concerned by this, later it is all skimmed off."