- 2 tbsp. olive oil
- 1 small yellow onion, halved and sliced into ¼-inch thick slices
- 1 tsp. crushed red pepper flakes (or start with ½ tsp. for less spice)
- 2 (28 oz.) cans whole tomatoes
- 1½ cups water
- ¼ cup loosely packed fresh basil leaves
- Kosher salt and freshly ground black pepper
step 1: Show Images
Add the olive oil to a large saucepan or Dutch oven over medium heat, and heat until shimmering. Add the onion and red pepper flakes to the pan and cook, stirring occasionally, until the onions are translucent and tender, about 10 minutes.
step 2: Show Images
Add the tomatoes with their juices and the water to the pan, and bring to a boil. Reduce the heat to low and simmer, stirring occasionally, about 30 minutes. (If you have less time, shorten the cooking time and add less water.) Add the basil, season with salt and pepper to taste, and let cool briefly, about 5 minutes.
step 3: Show Images
Set a fine mesh strainer over a large heatproof bowl. Add the contents of the saucepan to a blender or food processor and puree until smooth, venting the top to let the heat escape. Pour the soup through the strainer, pressing through to retain all of the liquid but remove the solids. Taste and adjust seasoning as necessary. Serve warm.