In a soup pot, sauté onions in olive oil until fragrant and lightly caramelized ~4-5 minutes.
Add garlic and herbs and cook for 1 more minute.
Add tomatoes and broth and bring to a boil. Cover and let simmer on medium-to-low heat for 15 minutes. Season with salt and pepper and remove from heat.
Pour into a high-speed blender and blend until smooth.
Transfer to serving bowls and garnish with thyme leaves or your topping(s) of choice.