Start by cleaning your mushrooms thoroughly to remove any dirt.
Finely chop the mushrooms to ensure they cook down evenly and create a smooth gravy.
Heat a large skillet over medium heat and add the butter and olive oil. Once the butter melts and starts to sizzle, add the chopped onion. Sauté the onion for 3–4 minutes, or until it turns translucent.
Next, stir in the minced garlic and cook for another minute. Add the chopped mushrooms to the skillet. Stir them well to coat with the butter and oil. Let the mushrooms cook for 8–10 minutes
Sprinkle the flour evenly over the mushroom mixture. Stir continuously for 1–2 minutes to cook off the raw flour taste.
Gradually pour in the vegetable broth while whisking constantly.
Add the soy sauce, dried thyme, rosemary, black pepper, and a pinch of salt. Stir everything together and bring the mixture to a simmer.
Reduce the heat to low and let the gravy cook for 5–7 minutes, or until it thickens to your desired consistency.
For a creamier gravy, stir in heavy cream or a plant-based cream alternative during the last minute of cooking.
