The idea is easy and ingenious: When tomatoes are pureed until skin and seeds are crushed into a smooth mash, jelling agents within the tomatoes are released. The resulting gel or mousse is quite fragile and is best served the same day.
The flavor of this dish depends on the flavor of the tomatoes. Using ripe heirloom tomatoes will give the best result. If your tomatoes are somewhat bland, a pinch of sugar, a pinch of salt and perhaps also a little vinegar can improve the flavor of the mousse.
Consult the manufacturer's directions for your blender to make sure running it for 5 minutes at a time is okay. If the blender seems to be overheating, puree in 1-minute increments.
The dish can be elaborated upon in a number of different ways: with a sprinkle of Parmesan cheese, a slice of mozzarella cheese underneath or some baked garlic alongside the basil oil.
- 8 medium or 4 large heirloom tomatoes, cored and cut into quarters
- Salt (optional)
- Sugar (optional)
- Red wine vinegar (optional)
- 1/3 cup olive oil
- 1/2 cup tightly packed basil leaves
- Fleur de sel
Place the tomato pieces in the blender; puree for about 1 minute, until completely smooth. Scrape down the sides of the blender jar as needed to make sure all the tomato is incorporated. Puree on the highest speed for 4 to 5 minutes (if possible; see headnote) in order to crush as many as the cells as possible. The mixture will be pinkish.
If desired, season with a little salt, perhaps also a sprinkle of sugar and a little vinegar. Puree for a few seconds and pour the tomato mixture into 4 wine or martini glasses. Refrigerate for 3 to 4 hours.
Before serving, combine the oil and basil in the blender and puree to a coarse consistency, scraping down the sides of the blender jar as needed to ensure all the basil is incorporated. Pour through a fine-mesh strainer into a small jar, using a spoon to press lightly on the basil pulp. Cover and refrigerate until ready to use.
When ready to serve, pour a small amount of the basil oil over each portion of tomato mousse and sprinkle with a little fleur de sel.
From Gastronomer columnist Andreas Viestad.
Tested by Frances Stead Sellers and Bonnie S. Benwick.
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