Savoury Mushroom Sauce

This is the dairy-free, gluten-free mushroom gravy that belongs in every plant-based cook’s back pocket. No butter, no flour roux, no cream. Just a deeply concentrated porcini extract thickened with arrowroot and seasoned with tamari, maple syrup, and rosemary. The flavor is unmistakably mushroomy, with a backbone that rivals any beef gravy.

The two-step build is what gives it depth. Dried porcini simmer in water for 15 minutes to make a near-black mushroom tea. That liquid becomes the base for the sauce. The rehydrated mushrooms get chopped and folded back in at the end, so every spoonful has both the concentrated broth and the texture of real mushroom pieces.

Arrowroot is used instead of cornstarch or flour for a reason. It thickens clear and glossy, doesn’t cloud the sauce, and stays stable even if reheated. Flour-based gravies go pasty when warmed up a second time. Arrowroot doesn’t.

Kitchen Tips

• Rinse the rehydrated mushrooms to remove grit. Dried porcini always carry sand from the forest floor.
• Strain the mushroom extract through cheesecloth or a coffee filter. Even one grain of sand ruins the sauce.
• Whisk the arrowroot with cold water first, then stir in. Adding dry arrowroot directly causes lumps.
• Don’t boil after the arrowroot goes in. Arrowroot loses thickening power at sustained boil, unlike cornstarch.

Variations

• Swap porcini for dried shiitake or a mix of dried mushrooms for different flavor notes.
• Add a splash of dry red wine or sherry with the onions for more complexity.
• Stir in a tablespoon of nutritional yeast for extra umami and a cheesy depth.