Gather the ingredients.

Melt butter in a large pot over medium heat. Cook mushrooms in butter in batches, turning occasionally, until golden brown, about 10 minutes. Add a portion of the garlic at the end of each batch and cook until fragrant, about 1 minute. Remove mushroom mixture to a plate.

Add onion to the pot. Cook and stir until onion has softened and turned translucent, about 5 minutes.

Add mushroom mixture, thyme, and parsley. Pour wine into the pot and cook while scraping the browned bits of food off the bottom of the pan with a wooden spoon, about 3 minutes.

Sprinkle flour over the mixture and stir until well incorporated.

Add broth, bouillon, salt, and pepper and bring to a boil. Reduce heat to low. Cover and simmer, stirring occasionally, until thickened, about 10 minutes.