Wash leg of lamb. Puncture in several places and insert thin slices of garlic clove. Sprinkle generously with oregano, coarse pepper and salt. Pour 1/2 cup olive oil and juice of 1/2 lemon or lime over meat.

Bake at 400 degrees for 30 minutes. Reduce heat to 325 degrees. Bake 3 to 3 1/2 hours (1 1/2 to 2 hours for half leg of lamb). Add water to baking pans as needed, 1/4 cup at a time. Squeeze the other half of the lemon or lime over meat 1 hour before it is done.