For BBQ and similar gatherings, I've found that a Melktert works great in most cases.
South Africans have a big barbecue/grill-out/braai culture and this one seems to be a real favourite. Make it up the night before, chill in the fridge and you're good to go.
There are thousands of recipes and variations online. Some like it thick and heavy, others go for light and fluffy.
I usually have to make a gluten-free version for the guests I have, but you can also do things like a chocolate version if you like. It's very versatile.