Homemade grapefruit dill cordial

Aris Makris’ recipe, good for 500 ml: place the pulp and zest from two grapefruits and 50 g of dill into a saucepan. Add 250 g of sugar and muddle, then let the mixture steep for no less than an hour. Pour 500 ml of still mineral water into the saucepan and bring to a boil. Let the resulting liquid cool, then filter into a separate container. Store in the refrigerator.