Toast 1/2 cup broken spaghetti in a saucepan with butter, 2 minutes. Add 1/2 cup chopped onion and cook 1 minute. Add 1 cup basmati rice and a pinch each of allspice and salt; cook, stirring, 2 minutes. Add 2 cups chicken broth; cover and simmer, 15 minutes. Cook 1/2 cup each sliced almonds and dates in butter, then stir into the rice. Season with salt and top with chopped parsley.