01 - Preheat oven to 350°F (180°C). Line a 12-cup muffin tin with paper liners or lightly grease each cup.
02 - Heat olive oil in a large skillet over medium heat. Add chopped onion and cook for 3 minutes until translucent.
03 - Stir in minced garlic and cook for 1 minute. Add diced mushrooms, thyme, and smoked paprika. Sauté for 6 to 8 minutes until mushrooms release moisture and are browned. Remove from heat and set aside to cool slightly.
04 - In a small bowl, mix soy or oat milk, vegan sour cream, apple cider vinegar, and Dijon mustard until smooth.
05 - In a separate large bowl, whisk together all-purpose flour, baking powder, baking soda, salt, and black pepper.
06 - Add the cooled mushroom mixture and chopped parsley to the dry ingredients. Stir to distribute evenly.
07 - Pour the wet mixture into the mushroom-flour blend. Gently fold until just combined; avoid overmixing.
08 - Divide batter evenly among the prepared muffin cups.
09 - Bake for 22 to 26 minutes, until a toothpick inserted in the center comes out clean and tops are lightly golden.
10 - Let muffins cool in the tin for 5 minutes, then transfer to a wire rack. Garnish with extra parsley before serving warm or at room temperature.