In a pan, warm the olive oil over medium heat until shimmering. Add the onion and salt and cook, stirring occasionally, until the onions are tender and turning translucent, 7 to 10 minutes. Add the tomato chopped and cook, stirring constantly, until fragrant, about 30 seconds.
Add the tomatoes puree, bay leaf, garlic, tulsi, black pepper, and stir to combine. Increase the heat to medium-high, and bring the mixture to a simmer. Cook for 30 minutes, reducing the heat as necessary to maintain a gentle simmer, and stirring occasionally.
Remove the pot from the heat and let it cool for a few minutes. transfer the mixture to a blender, being sure not to fill paste the maximum fill line. Securely fasten the lid and blend the soup until smooth, being careful to avoid hot steam escaping from the lid.
Since canned tomatoes vary in flavor, I always end up tinkering with this soup a bit at the end. Add pepper, and salt Briefly blend again, and serve hot.
