The best thing about hosting your 30th birthday party at a bar is that you don't have to worry about making cocktails. Talk to the management and make arrangements for either an open bar, a wine/beer/specialty cocktail bar, or a no hosts bar in which guests pay for their own drinks.
For DearSugar's 30th birthday at Le Colonial, the bar will be open. One of the cocktails that's on the extensive cocktail menu is a delicious blend of orange flavored vodka and fresh passion fruit. To take a look at the recipe,