tailgating for a Bruce concert - about 35-40 people!
This will sound weird but . . . a platter of chilled, assorted veggies that have been blanched - served with dipping sauce (my favorite is Indonesian peanut sauce from the Moosewood Cookbook). With all the starchy side dishes and meats that are usually available at tailgates, you'd be surprised how many people are anxious to gobble up some veg. And blanching the veg makes it more interesting than the usual crudite . . .
Some ideas that have worked for me:
Muffuletta style sandwiches -- make cold cut sandwiches with the olive/veggie spread the night before on either a large round bread (to serve in wedges) or long bread suitable for a sturdy sub. For a crowd that large, I might also make one with only grilled/roasted veg and cheese for those that don't want the meat. No cooking involved and meant to be made the night before.
Some other tailgate standbys:
~Kielbasa slices seared and then simmered with some white wine and grainy mustard – great with toothpicks served at room temp.
~A “do it yourself” Cesar, Cobb, or Nicoise salad when I had guests that I knew were picky – made a great homemade dressing but put most of the additions on the side.
~Gazpacho in hot weather or tomato basil soup in cold weather (both can have vodka added in a bloody mary sort of thing).
~Pork rillettes (garlicky and well seasoned) sandwiches on dark bread with mustard, pickled red onion and lettuce.
~Whole coconuts and a drill, with dark rum to pour inside.
~Fruit crisp for desert – depending on the season it could be peach, apple, pear, etc. A crisp is great for a crowd and serves well at room temp.
~Fruit salad of any sort, but I have a melon salad with lemongrass dressing that is quite nice.
Have a great time at your concert!
I'm guessing that you won't have any cooking/heating facilities. If that's correct, maybe...
Pre-made deli type sandwiches
Salads, dressed on site, cole slaw, corn and bean, three bean, pasta, potato; many salad choices
Crudite platter, chips and dips
Ham wrapped cheese chunks
Cup cakes, brownies, cookies
...and wine, lots of wine
For something you can just enjoy cold try making a cornish pasty.
You can easily increase the recipe and/or alter the size of the pasty to suit your group size, plus you can make this is an assembly line style once you have your elements ready.
If you want something hot, what facilities do you have on the road?
Musie - your reply is another reason why I value this site and our fellow chowhounders - I am always learning new and interesting things - thanks for introducing me to the Pasty - and the swede - our version of ruttabaga/turnip which I learned from google! I will definitely be trying this another time!