Heat the olive oil in a large pot over medium heat. Add the diced onion and minced garlic, sautéing until translucent and fragrant, about 3-5 minutes, until the onions are soft and beginning to brown.
Add the chopped tomatoes to the pot and cook for another 5 minutes, stirring occasionally, until the tomatoes soften and release their juices, creating a vibrant red mixture.
Pour in the vegetable broth, increase the heat to bring the mixture to a gentle simmer. Cook uncovered for 10 minutes, allowing flavors to meld and the tomatoes to fully break down.
Use an immersion blender to carefully blend the soup directly in the pot until smooth and velvety, with no visible chunks. Alternatively, transfer the mixture to a blender in batches, then return to the pot.
Stir in the heavy cream and season with salt and pepper to taste. Continue cooking on low for 2-3 minutes until heated through, and observe the soup develop a glossy, creamy appearance.
Serve hot, garnished with fresh herbs or a drizzle of olive oil if desired, showcasing a smooth, vibrant red consistency with a silky finish.
