In traditional Chinese medicine, a deer penis (Vietnamese: Lộc pín; Chinese: 鹿鞭; pinyin: lù biān) is said to have important therapeutic properties.(Wikipedia).

Some methods of preparation
The penis is sliced and soaked in rice wine or whisky. A shot of it should be taken once every one or two weeks.
To prepare a pizzle for cooking, first blanch with ginger, spring onion, rice wine, tea leaves, and, if possible, fresh bamboo shoots. Then simmer them with chicken and purifying seasonings. The pizzles can be simmered in a Chinese clay pot for five and a half hours,with a whole chicken, more wine, ginger, spring onions, Sichuan peppercorns, and a bunch of Chinese tonic herbs: licorice, milk vetch root, dried yam, and Chinese sage. Or they can be stir-fried with sliced pork belly, and then stewed for several hours in a sauce of chili bean paste, with Shaoxing wine, cassia bark, and star anise. (original article here)