How do you use "Lemon Palm as a spice?

Question

I think I found some in a old garden that I use now

Answer 1

If peter is right and you mean "balm" this is what I've found and copied -
Culinary Uses
Because of its delicate lemon flavour, lemon balm has a wide culinary potential. Apart from using fresh leaves as an attractive garnish, Chopped fresh leaves can be used to to add zest to sweet or tangy dishes. It combines well with allspice, bay leaves, mint, pepper, rosemary and thyme. Fresh herbs with essential oils, however, are less potent and should be added at the end of cooking. A wonderful addition to fruit salads, green salads, herb butters, fruit drinks, sorbets. It can also be used in egg dishes, custards, soups and casseroles. It works well in stuffings for poultry,lamb or pork. Its subtle flavour is a perfect for sauces and marinades for fish. Lemon balm and chervil are also good combination.
Lemon Balm is the basis of the cordial eau des Carmes and is also found in Benedictine and Chartreuse

Answer 2

Do you mean Lemon Balm? If so, try crushed fresh leaves steeped in iced tea or lemonade for a hot-weather drink. It's also good added to vegs, baked fish or chicken, and fruit salads.

Answer 3

I think you mean lemon balm, or melissa. This herb (not a spice) is commonly used dried as a tea, or fresh as a garnish.