Tarquin's Cornish Pastis is produced at the Southwestern Distillery in Cornwall, England, and is characterized by limited production, with each batch consisting of only 300 bottles. This spirit is produced by traditional pot still distillation and consists of a carefully selected blend of ingredients.

The main ingredients include green aniseed and licorice, complemented by coriander seeds, juniper berries, angelica root, orris root, cardamom, cinnamon and hand-picked gorse flowers from the region. Orange, lemon and grapefruit peel is also added. Each bottle of Tarquin's Cornish Pastis is bottled by hand, labelled, sealed with wax and signed, which emphasizes the artisanal quality of the product.

Pastis was created as a reaction to the ban on absinthe in France in 1915 and was developed in Provence by local farmers. The term "pastis" comes from the Provencal word for "mixture" and from the French word for "imitation". A characteristic feature of pastis is the louche effect, a milky cloudiness that occurs when water is added. This is due to the release of essential oil, anethole, which is insoluble in water, releasing the oils previously enclosed by the alcohol and clouding the liquid by refraction.