Pesto can easily be made at home but you do need a generous amount of basil leaves to make just a small portion of pesto. Variations include using rocket, watercress or parsley instead of basil and nuts such as walnuts, hazelnuts or pistachios instead of pine nuts. The sauce can be stirred into freshly cooked pasta, spooned on to thick soups, spread on bruschetta, fillets of fish or chicken before grilling, or added to mayonnaise and salad dressings.