Drain garbanzo beans, reserving the liquid. In a blender or food processor bowl, combine beans and 2 tablespoons of the reserved liquid, the walnuts, basil leaves, olive oil, lemon juice, salt, and pepper.
Cover and blend or process until nearly smooth. (Scrape down sides and add additional reserved liquid if mixture appears stiff.) Serve on toasted baguette slices or pita slices. Store, covered, in the refrigerator up to 5 days. Makes about 1-1/4 cups.