Name: Mushroom Catsup
Ingredients: full grown mushrooms; coarse sea salt

Mushroom Catsup

Ingredients

full grown mushrooms
coarse sea salt

Directions

Layer mushrooms in a deep earthen pan, sprinkling each layer with coarse sea salt.
Repeat layering mushrooms and salt for two to three hours.
Mash the mushrooms well and let them sit for two days, stirring and mashing occasionally.

Recipe from a historical cookbook (Internet Archive).

Transcribed from a scanned cookbook and modernised for today's kitchens. Where the book gave no heat or time, or said "a moderate oven", the temperatures and times here may be modern equivalents rather than the book's own figures.