In a large Dutch oven or heavy pot, melt butter and olive oil over medium heat. Add the chopped onion, carrots, celery, garlic, ½ teaspoon salt and sauté until the vegetables start to soften, about 5-7 minutes.
Sprinkle a.p flour evenly over vegetables and cook, stirring often, for 1 minute. Pour in the wine to deglaze the pot, scraping off the bottom if needed. Bring the wine to a bubble to burn off the alcohol about 3 minutes.
Add the thyme, broth, cauliflower, bring the pot to a boil, then drop the heat to simmer, cover and cook for 15-18 minutes. If you're adding potatoes cook for another 5 minutes until the potatoes are cooked through.
Remove the lid from pot and transfer the 1 cup vegetables and about 1 cup of the soup to a blender and blend until smooth.
Transfer puree back to the pot. Add the milk, corn, and smoked salmon and cook for about 5 minutes.
Taste and season as necessary. Ladle into bowls and serve garnished with freshly ground pepper, chopped chives and a few salmon flakes. enjoy!