What is the best recipe for group of 15 in summer?

I love grilling various kababs, like marinated chicken, beef, shrimp and various vegetables.

thank you all very much for your answers!!

sounds like a great party, Abbie!
In summer, I like to do tacos - grill spicy shrimp and flank steak, make Merrill's salpicon. Make guacamole, beans and rice and cabbage slaw. Maybe a red and green salsa and let people fill corn and flour tacos.

Things I am serving for my BDay shindig, which will be indoor/outdoor and have just about that many people:

http://food52.com/recipes/17913-charred-corn-and-avocado-salad-with-lime-chili-and-tomato

http://food52.com/recipes/12121-summer-squash-salad-with-mustard-mint-aioli

http://food52.com/recipes/12654-finger-lickin-finger-lakes-chicken

also pickled shrimp, grilled lamb chops, some slaw, and as many cakes as I can get people to bake and bring!

Forgot to mention, use different breads from regular sliced for kids, to croissants, whole wheat, seeded etc for adults. Individually wrap with parchment paper and twine for eye appeal.

Consider a sandwich buffet table - ham and cheese etc for adults, PB&J for kids. A couple salads, some cookies. (keep everything on ice until serving)

More info please! What sort of occasion - indoors or outdoors? Day or night? All adult or children too? And themes or dietary needs?