Soak dried mushrooms in veggie broth. Set aside.
1 cup dried wild mushrooms, 1 ½ cups vegetable broth
Heat some olive oil in a large saucepan over medium heat.
Add onion and celery and saute until onion is golden brown and translucent.
1 white onion, 1 celery stalk
Add the garlic and chopped mushrooms. Season with salt.
4 garlic cloves, 12 oz chopped cremini mushrooms (~4 heaped cups (chopped), ½ teaspoon salt
Fry mushrooms on medium-low heat until all the water has evaporated (around 10 min). Season with thyme and paprika powder.
½ teaspoon thyme, ½-1 teaspoon paprika powder
Add the soaked mushrooms (including the soaking liquid).
In a jug, dissolve corn starch into ⅓ cup veggie broth. Then add the sour cream and whisk again until fully dissolved.
1 heaped tablespoon sour cream, ⅓ cup veggie broth, 1 tablespoon corn starch
Add the mix to the mushrooms and let simmer for 3-5 more minutes for the sauce to thicken slightly.
Taste and season with salt and black pepper. Serve over mashed potatoes, pasta, rice or a baked potato.