01 - Preheat your oven to 375°F (190°C) to prepare for baking the croutons.
02 - In a large heavy-bottomed pot or Dutch oven, warm 2 tablespoons of olive oil over medium heat. Add the finely chopped yellow onion and sauté, stirring occasionally, until it becomes translucent and softened, approximately 5 minutes.
03 - Incorporate the minced garlic into the pot and cook for an additional minute until it becomes aromatic, being careful not to brown it.
04 - Stir in the crushed tomatoes, tomato paste, vegetable broth, sugar, salt, and freshly ground black pepper. Bring the mixture to a gentle simmer, then reduce heat and cook for 15 minutes, stirring periodically to prevent sticking, allowing the flavors to meld.
05 - While the soup simmers, prepare the croutons. In a large mixing bowl, combine the 3 cups of day-old bread cubes with 2 tablespoons of olive oil, ½ teaspoon of garlic powder, ½ teaspoon of salt, and ¼ teaspoon of black pepper, tossing to ensure even coating. Spread the seasoned bread cubes in a single layer on a baking sheet. Bake for 10–12 minutes, turning halfway through, until they are golden brown and crisp. Remove from oven and set aside.
06 - Once the soup has completed its simmering time, remove the pot from the heat. Stir in the ½ cup of chopped fresh basil leaves.
07 - Carefully use an immersion blender to puree the soup directly in the pot until it reaches a velvety smooth consistency. If using a standard blender, work in small batches, filling the blender no more than halfway, and blend until smooth. Return all pureed soup to the pot.
08 - Return the pureed soup to low heat. Gently stir in the 1 cup of heavy cream and heat through for 2–3 minutes, ensuring it does not come to a boil, which can cause the cream to separate.
09 - Taste the bisque and adjust any seasonings as necessary, adding more salt or pepper to your preference.
10 - Ladle the warm creamy tomato basil bisque into individual serving bowls. Garnish with additional fresh basil leaves and a generous handful of crispy homemade croutons just before serving.