“Never wash mushrooms. They’ll be a soggy, gelatinous mush.” So goes conventional wisdom about handling fungi in the kitchen. “Ridiculous,” Chris Czarnecki scoffed. “Of course you should wash mushrooms. “I have a picture of my grandfather in a bathtub of cold water filled with mushrooms. He washed mushrooms every day.” Lest you wonder why Czarnecki’s grandpa would be posing in a tub full of mushrooms to begin with, Joseph Czarnecki, Jr. was the second-generation patriarch of the first and still only mushroom culinary dynasty in the United States. His father opened Joe’s Tavern in Reading, Pennsylvania, in 1916; when Joe Jr. (Chris’s grandfather) took over, he refocused it to fine dining and boosted the emphasis on gathering and using mushrooms—just as their ancestors had done for centuries in Poland. By mid-century, it garnered a reputation as a mushroom citadel. Czarnecki’s father, Jack, moved the family business to Oregon’s Willamette Valley …