Add the crushed tomatoes, chopped onion, minced garlic, vegetable broth, and olive oil into your crockpot. Stir to combine everything evenly.
Sprinkle in the smoked paprika and season with a pinch of salt and pepper. Stir gently to distribute the spices.
Set the crockpot to low and cook for 6 to 8 hours. During the first hour, give it a gentle stir every couple of hours to prevent sticking and help flavors meld.
Once the cooking time is up, use an immersion blender directly in the crockpot to puree the soup until velvety and smooth. Alternatively, carefully transfer the soup in batches to a blender and blend until smooth, then return to the crockpot.
If you prefer a creamier soup, stir in the cream or milk now, and let it warm through for a few minutes.
Taste the soup and adjust salt, pepper, or add a squeeze of lemon for brightness if needed. The soup should smell rich with smoky tomato aroma and be velvety in texture.
Serve hot, garnished with a drizzle of olive oil or fresh herbs if desired. Pair with crusty bread or grilled cheese for a complete cozy meal.
