In a food processor, combine the blanched almonds, pine nuts, garlic cloves, and salt.
Process until the nuts are finely ground.
Add the 4 cubes of melon and continue processing until smooth.
Soak the slices of bread in water, then squeeze them dry.
Gradually add the bread to the food processor while it's running, processing until smooth.
With the processor still running, slowly drizzle in the olive oil until fully incorporated.
Then, add the sherry vinegar or red wine vinegar.
Gradually pour in the cold water while continuing to process until everything is well incorporated.
Strain the mixture through a fine-mesh strainer into a medium bowl to ensure a smooth texture.
Taste the gazpacho and adjust the seasoning with more vinegar or salt if necessary.
Cover the bowl and refrigerate the gazpacho for at least 2 hours, or overnight, to chill and allow the flavors to meld.
Before serving, taste the gazpacho again and adjust the seasoning if needed.
Pour the chilled gazpacho into individual bowls and float the small cubes or balls of melon in the soup.
Serve the gazpacho cold.