I started making this in winter when I didn't have fresh herbs so I topped with homemade basil oil which complimented this perfectly.
The Food Lab by J. Kenji Lopez-Alt
5 tablespoons unsalted butter
1 1/2 cups onion, finely diced
1 pinch red pepper flakes
1/2 teaspoon dried oregano
1 tablespoon all-purpose flour
2 cans 28 ounce whole tomatoes , with juice
1/2 cup whole milk or heavy cream
black pepper, freshly ground
2 tablespoons whiskey, vodka, or brandy
2 tablespoons extra virgin olive oil
2 tablespoons chopped fresh herbs - parsley, basil or chives
1. Melt the butter in a medium saucepan over medium-high heat. Add the onions and cook, stirring frequently, until softened but not browned, 6 to 8 minutes. Add the pepper flakes and oregano and cook, stirring, for 30 seconds. Add the tomatoes, with their juice, and stir, scraping the flour up off the bottom of the pan. Add the milk or cream and cook, stirring occasionally and breaking up the tomatoes with the spoon, until the whole thing comes to a boil. Reduce to a simmer and cook for 3 minutes.
2. Remove the soup from the heat and puree using an immersion blender. Or transfer to a standing blender, in batches if necessary, and puree, staring on low speed and gradually increasing to high, then return to the pan. Season the soup to taste with salt and pepper. Stir in the whisky, if using, and bring to a simmer. Serve immediately topping each serving with a generous drizzle of olive oil, a sprinkle of herbs, and if you like a crack or two of freshly ground pepper, with grilled cheese sandwiches alongside.