Check out the Vegan Ice Cream Review thread for non dairy ideas for your Ice Cream cake!  I really want to make one for myself with crushed Newman O's in the middle of the layers.

If you are comfortable making spring rolls how about expanding on that idea?  Have some simple summer rolls with lightly blanched veggies wrapped in rice paper.  Make some with fruit too as a dessert option.  Make some cold noodles with dipping sauce.  Serve some edamame either warm in the pod or in a salad; spinach, quinoa, edamame, mini corn, water chestnuts, soy sauce and rice wine vinegar with a tiny bit of uemboshi paste mixed in and sesame seeds.  You could try your hand at making dumplings too!  Or seitan pot stickers.

If that is too much of a theme for you than go with what you know and love.  Make your favorite casserole or main dish.  Serve it with roasted veggies sprinkled with your favorite herbs like basil or garlic or smoked paprika.  Serve a salad with dressing options, fruit salad and your dessert.

If my daughter wanted me to cook for her 18th birthday party for our family and friends I would go with favorites that pair well with the season (summer heat) and atmosphere (casual and family fun).  Veggie trays with vegan ranch dip, marinated mushrooms and olives would be first.  Next would be a big cold salad of quinoa, corn, edamame, avocado, lime and cayenne.  After that the main course of BBQ Seitan Ribz, chickpea cutlets, herb roasted potatoes, grilled veggies like portobella mushrooms, zucchini, bell pepper, and corn.  To finish off some grilled pineapple rings, grilled peaches, cake and ice cream.

When I grill veggies I like to season them right before putting them on the grill.  Sometimes its a touch of balsamic and basil.  Other times its thyme and a brush of olive oil.  Lately its garlic and smoked paprika.  Its all in what you like.

Happy birthday!