Heat a large heavy-bottomed pot over medium heat. Add 2 tbs olive oil and 1 tbs butter. When butter melts and is foaming, add the finely diced onion, carrot, and celery. Cook, stirring occasionally, until softened and translucent, about 8–10 minutes. Add the minced garlic and cook 30–45 seconds until fragrant.

add tomatoes and simmer

Stir in the crushed tomatoes, tomato paste, sugar, dried oregano, and bay leaf. Pour in the stock. Bring the mixture to a gentle simmer over medium-high heat, then reduce to low. Simmer uncovered for 20–25 minutes to let flavors meld and slightly reduce.

Blend & Finish

remove bay leaf and blend

Remove the bay leaf. Use an immersion blender to puree the soup until smooth and silky, or carefully transfer the soup in batches to a blender and puree until smooth, then return to the pot.

finish with cream and seasoning

Over low heat, stir in 1 cup heavy cream and 1 tbs butter. Warm gently — do not boil — until the soup is heated through and slightly thickened, about 3–5 minutes. Stir in the sliced basil (reserve a few leaves for garnish), 1.5 tsp kosher salt, 3/4 tsp freshly ground black pepper, and 1 tsp lemon juice if using. Taste and adjust seasoning.

Crostini & Garnish

toast crostini

Preheat the oven to 400°F (200°C). Arrange baguette slices on a baking sheet and brush both sides lightly with 2 tbs olive oil. Toast in the oven until golden and crisp, about 6–8 minutes, flipping once halfway through. Remove from oven and, while still warm, rub one side of each slice with the cut garlic clove and sprinkle a light pinch of fleur de sel over the slices.

assemble and serve

Ladle the soup into warmed bowls. Crumble about 0.5–1 oz gorgonzola over each bowl (reserve remaining for additional bowls). Float a small basil chiffonade and a drizzle of olive oil if desired. Serve crostini on the side or perched on the bowl edge so they stay crisp. Garnish with remaining crumbled gorgonzola and basil leaves. Serve immediately.