Step 1

Peel the peaches and tomatoes using a sharp paring knife (the skins should come off fairly easily if ripe) or by briefly blanching in boiling water.

Step 2

To blanch peaches and tomatoes make a small slit with a paring knife at the base of each. Gently lower into a large pot of boiling water for 30 seconds. Using a slotted spoon remove the peaches and tomatoes from the hot water, and plunge into an ice water bath to cool. The skins should slip off.

Step 3

Combine the peeled peaches and tomatoes with a pinch of salt and four or five large basil leaves in a blender along with the lime juice and lime zest. Blend on high until smooth and finely pureed. Taste and season with additional salt if needed. Refrigerate until well chilled (at least 2 hours).

Step 4

Meanwhile make the pistachio basil pistou by pulsing together the shelled pistachios and four or five basil leaves with a pinch of salt in a small food processor or finely chop by hand with a sharp chef’s knife . Add the pistachio oil and pulse until just combined or stir into the finely hand chopped basil and pistachios.

Step 5

Serve soup in chilled bowls or glasses topped with the pistachio basil pistou.