Finely chop the feverfew leaves, parsley and tarragon together on a wooden board. Add the ginger and lemon zest. Mix into the soft butter and add salt and pepper to taste, and work until the herbs are evenly distributed throughout the butter. Place the herb butter on a sheet of greaseproof paper and form into a long sausage shape. Mark lightly into seven equal portions, enough for a week's supply. Roll up the paper and seal at both ends. Eat one portion daily on bread or toast to prevent migraine. Do not use if you are pregnant or breastfeeding, under 18, or have a stomach or mouth ulcer. If on medication, check with your doctor or pharmacist before using. Discontinue if you feel nausea or other discomfort. As with other painkillers after long-term use, you might experience 'rebound' symptoms such as headaches when you stop. If so, consult your doctor or pharmacist. The butter will keep in the refrigerator for 1 week or in the freezer for up to 6 months. The content of this program is for entertainment purposes only, and is not intended as medical advice. Always consult a professional healthcare provider before trying any form of therapy or if you have any questions or concerns about a medical condition. The use of natural products can be toxic if misused, and even when suitably used, certain individuals could have adverse reactions.