Step into Madeleine’s Candy Shop to find an array of squishy, tutti-fruity, sugar-dusted, sweet-and-puckery gummies in a rainbow of hues.

From hearty comfort foods for those long, winter nights, to seafood dishes with a twist, Stockholm offers plenty of ways to experience Swedish food firsthand.

But a small, active and aging group of locals are preserving the city’s Swedish food traditions for a new generation. Without them, who would pickle the herring or import the lye-soaked lutefisk?

The extent of most Americans’ experience with Swedish food is Ikea meatballs with lingonberries, and to be sure Warnelius-Miller family does enjoy eating and making them, with Justin sometimes ...