When greasy poutine with cranberry ketchup is the salad course, you know you’re in for a raucous meal. But Pocket Brunch pop-ups in secret locations around Portland only one Sunday a month, so it’s worth indulging. The hardest-to-come-by seat in town is the brainchild of Katie and Josh Schier-Potocki, co-owners of South Portland’s 158 Pickett Street Café. Last month, a select sixty-five sat at red gingham-clad tables, dining on five French-Canadian courses, served on paper plates. The “Bienvenue” fête filled an industrial space the couple, expanding their catering and bakery operations, now shares with their friends at the SoPo Wine Co.