Final answer:
If a guest requests ice cream and it's not available, offer them the chance to make homemade ice cream using heavy cream, whole milk, sugar, and their choice of flavor, or you could suggest an alternative like the brownies you have on hand.
Step-by-step explanation:
If a guest wants ice cream for dessert and you know that scoops of ice cream are not available, you could suggest an alternative dessert that you do have available, such as the brownies mentioned in the scenario. If the guest is still keen on ice cream, you can offer them the unique experience of making homemade ice cream. You can explain that with heavy cream, whole milk, sugar, and their choice of flavor, they can create their own ice cream using simple tools and ingredients.
Making homemade ice cream can be a fun activity and it allows the guest to personalize their dessert. Furthermore, by preparing it themselves, they can appreciate the physics involved in the process. Since you already have a dessert option covered with the brownies brought by one of the guests, this DIY approach to ice cream could be an entertaining and satisfying alternative for those who wish for something different.