If your guest is on Warfarin, the guidance is to avoid foods rich in Vit K because those foods are good for blood clotting, good under normal circumstances but not for Warfarin patients because it is designed to impede clotting for heart and circulatory conditions and post-bypass operations.
Also bear in mind the adverse effect of alcohol, so best to avoid serving it.
Avoid List
amaranth leaves
asparagus
broccoli
Brussels sprouts
coleslaw
collard greens
canned beef stroganoff soup
endive
garden cress
kale
kiwifruit
lettuce
mustard greens
soybeans
spinach
Swiss chard
tuna fish in oil
turnips
vegetable drinks
From www.medicalnewstoday.com/articles/324419.php
Warfarin can help to prevent dangerous blood clots. It works by slowing the production of clotting factors, which the body makes by using vitamin K from food. Levels of vitamin K in a person's diet could influence the effects of warfarin
People taking warfarin must avoid eating too many foods that are high in vitamin K, but it is not necessary to avoid these foods entirely. A stable diet, containing around 60 to 80 mcg of vitamin K is desirable
People on warfarin must also ensure that they only consume alcohol in moderation. High levels of alcohol may affect the metabolism of warfarin and increase the risk of major bleeding