Heat the oil in a pot over medium heat. Once hot, add the mushrooms and cook for 6-8 minutes, or until starting to turn golden, stirring occasionally. If the mushrooms release a lot of water, increase the heat to help it evaporate.
2 teaspoons oil, 200 grams (2 cups) mushrooms
Reduce the heat to low-medium and add the onion. Cook for another 6-8 minutes. If the onions start to catch, reduce the heat even more.
1 small onion
Add the garlic and cook for another two minutes, then stir in the spices. Add the wine. Stir to release any bits that have stuck, then let the wine simmer for five minutes to reduce. It should be almost dry again after the five minutes (see step-by-step photos in above post).
1 clove garlic, ½ teaspoon sea salt, ½ teaspoon black pepper, ¼ teaspoon smoked paprika, 100 ml (⅓ cup) dry white wine
Add the stock or broth. Cover the pot and simmer (increasing the heat if needed) for another ten minutes.
250 ml (1 cup) mushroom stock
Whisk the corn starch and water together in a dish. Do not add starch without mixing with water first. Pour the mixture into the gravy, stir well, and simmer for another minute to thicken, then taste and season if needed. Serve hot.
1 tablespoon corn starch mixed with 1 tablespoon water
Leftover mushroom gravy can be kept in a sealed container in the refrigerator for up to three days and freezes well.
Notes
Every broth type will have a different level of salt, so consider the amount listed in the recipe card as a starting point. Taste the gravy and add more salt if needed before serving - it's better to have too little at the beginning than too much!