Full Gallon Recipe

Combine sugars and water

In a large heavy pot (at least 2–3 gallon capacity), add 1 liter of the filtered water and all sugars: light corn syrup, granulated sugar, and molasses. Stir to combine.

Heat and dissolve

Place pot over medium heat. Warm gently, stirring occasionally, until sugars are fully dissolved and mixture is smooth (do not boil vigorously). This should take about 6–8 minutes.

Add aromatics

Add fresh ginger slices, whole cloves, and ground cinnamon to the syrup. Simmer gently for 10 minutes to extract flavor, stirring occasionally.

Strain aromatics

Remove pot from heat and strain the syrup through a fine-mesh sieve or cheesecloth into a large, clean container or another pot to remove ginger and cloves. Press solids to extract liquid, then discard solids.

Add citrus, salt and vanilla

While the syrup is still warm (but not hot), stir in the lemon juice, lime juice, sea salt, and vanilla extract until fully incorporated. Taste and adjust: salt should be faintly perceptible, acids bright but not sharp.

Dilute to volume

Measure the total liquid you have. Slowly add the remaining filtered water (cold or room temperature) until the mixture reaches 1 gallon (3.785 liters). If you do not have a vessel marked in liters, pour into a clean 1-gallon jug or container. Stir or gently invert the container to homogenize.

Optional additions

If using, whisk in the cold-brew coffee or strong brewed tea for depth, and/or caramel syrup for color and rounded sweetness. Stir thoroughly to combine.

Chill

Allow the gallon to cool to room temperature, then refrigerate at least 4 hours or overnight to let flavors meld. Chilling also helps suspension of any fine particulates.

Final adjustment

After chilling, taste and adjust: if too sweet, add up to 1/2 cup water and a tablespoon lemon juice; if too tart, add up to 2 tablespoons simple syrup. Stir to incorporate.

Serve

Serve over plenty of ice (or chilled glasses). Garnish individual servings with lemon or lime wedges and a light dusting of cinnamon if desired. Keeps refrigerated up to 7 days; shake or stir before serving.