Just how much do you want to impress them? Here's one that will probably turn some heads.
Take a three pound pork butt roast and cook it over a divided bed of charcoal, with some good fruit wood such as apple or cherry thrown over the coals for smoke, on a covered grill for about thirty minutes, with the vents closed half way. Remove the roast from the grill and throw it into a slow cooker on the low setting, and let it sit in there with some sliced onion overnight. Before the picknic, take a fork and shred the pork, stirring int the juices. Bring along a honey/mustard based bbq sauce, a tomato based bbq sauce, and a mayo based bbq sauce with some horseradish, and some hamburger buns. This is gauranteed to please all comers.
If you want to take it a step or two up, a beef roulaide made from flank or skirt steak (well marbled), stuffed with a good bread dressing, or fruit dressing, or if you really want to impress, a lobster or crab stuffing, and slowly barbecued over a divided bed of coals and served hot will really impress.
For veggie sides, you could bring pre-cooked phyllo cups, filled with fruit and whipped cream, or a fruit salad served in a hollowed out watermellon.
Devilled eggs is always a hit as well. And everyone appreciates a great leafy sallad with good salad dressings such as ranch, or raspberry vinagarette.
Hope you find something to inspire you from what we have all posted.
seeeeeya; Goodweed of the North