Make the ginger syrup base. Place the grated ginger and honey in a small heatproof mug or bowl. Pour over 50ml of boiling water from the kettle. Stir vigorously with a teaspoon until the honey has completely dissolved — you should see the liquid turn from cloudy to a clear, amber-tinted syrup, and you’ll smell the sharp, peppery aroma of the ginger rising up.

Steep and strain. Let the mixture sit for 2 minutes. The water will deepen in colour to a pale gold, and the ginger bits will settle at the bottom. Pour the syrup through a fine-mesh sieve into your serving glass, pressing gently on the ginger pulp with the back of a spoon to extract every last drop of flavour. Discard the spent ginger — you should be left with about 60ml of smooth, fragrant syrup.

Add the lemon juice. Squeeze the fresh lemon juice directly into the glass with the syrup. Stir once; the colour will brighten slightly, and the sharp citrus scent will cut through the sweetness of the honey. This is your concentrated mocktail base.

Fill with ice and water. Drop a handful of ice cubes into the glass, filling it about three-quarters full. Pour over the cold water (or sparkling water) until the glass is nearly full. Watch the liquid swirl from dark gold to a pale, translucent lemonade colour as the ice chills it rapidly.

Garnish and serve. If using, rub the mint leaves between your fingers to release their oils, then drop them in. Float the lemon slice on top. The first sip should be cool, with a gentle tingle from the ginger and a bright, clean finish from the lemon. Drink immediately, while the ice is still clinking against the glass.