A classic French Pistou, originating in the Provence region of France, is basically a pesto without nuts. In it's most simplistic form pistou is made from basil, oil and garlic.
Place all ingredients in a food processor and process until relatively smooth. (NOTE 2)
Taste and add salt & pepper if necessary.
Notes
One clove of garlic can be replaced by 1 teaspoon of garlic paste.
If you don't have a food processor, you can use a mortar and pestle. Start with the basil, garlic and some olive oil. Add more oil, and the rest of the ingredients.
Keep the Pistou in a sealed jar in the fridge for up to 3 days.