One’s sorely tempted to praise the delightful new musical Waitress using lots of bakery metaphors. After all, its hero is a pastry genius with relationship woes named Jenna (Jessie Mueller). She’s a perky Southern gal who can confect a mouthwatering Mermaid Marshmallow Pie but can’t measure the right ingredients for happiness. So, unable to resist, here I go: Fresh and delicious, Waitress has an excellent ratio of sweet to tart; supporting characters who provide crustiness (Dakin Matthews’s grumbly store owner) and flakiness (Christopher Fitzgerald’s loony admirer of another waitress); and cooked-to-perfection staging by Diane Paulus. The whole dish is—please forgive me—love at first bite.