Cook the black-eyed peas in 4 cups of water, covered for 45 minutes or until tender, then drain. Cook the macaroni in boiling water for about 10 minutes. Drain and refresh under cold water. Bring the milk, oat bran, nutmeg and pepper slowly to a simmer, whisking constantly so that the oat bran does not burn. Cook gently for 2 minutes. Add the black-eyed peas, macaroni, and cheese to the sauce and simmer, mixing thoroughly for 2 minutes or until everything is hot throughout.