Heat the 480ml of water to 75–80°C — a cooking thermometer confirms the correct temperature; alternatively, bring water to a full boil and allow to cool for 5–7 minutes, which reduces the temperature to approximately the correct range. This temperature range is the same applied in the Peach White Tea Spritzer Mocktail and for the same specific reason: white tea's catechins and tannins extract differently from black and green tea at this temperature, producing the specifically soft, floral, lightly tannic character of white tea rather than the sharper, more robustly tannic result of boiling-water extraction. At 75–80°C the pleasant volatile aromatic compounds extract ahead of the harsh tannins; at boiling temperature the harsh tannins extract rapidly within minutes, producing a bitter result that is inappropriate as a base for a delicate fruit tea. Add the 2 white tea bags and steep for 3–5 minutes. The 3-minute point produces a delicate, very light, specifically floral cup; 5 minutes produces a more structured, slightly more tannic result with more body. Remove the tea bags without squeezing — squeezing releases the highest-tannin, most astringent concentrated liquid from within the bags. Allow the brewed tea to cool completely to room temperature.

Roughly chop the 3 ripe peaches — skin on, stones removed — into 3–4cm pieces. The skin-on approach contributes the concentrated aromatic compounds on the peel surface to the syrup during cooking, in the same way as the peach-skins-on approach in the Peach Rosemary Sparkling Mocktail produces more aromatic depth than peeled peach. Combine the chopped peaches, 120ml of water, and 35g of granulated sugar in a small saucepan. Place over medium heat and bring to a gentle simmer. Cook for 10–12 minutes, stirring occasionally and using the back of a spoon to lightly mash the peach pieces as they soften — pressing them against the pan's surface to release their juice and aromatic compounds into the surrounding liquid. The syrup should smell specifically fresh and peachy throughout this cooking period — a vivid, warm, fruity aroma rather than the heavier, caramelised-fruit smell that harder simmering or longer cooking produces. The distinction matters: the goal is the fresh, aromatic peach syrup that still tastes of the fruit rather than of cooked peach preserve.

Remove the saucepan from the heat. Immediately add the 5 fresh thyme sprigs. Allow to infuse covered for 8–10 minutes exactly. The thyme infusion timing in the warm off-heat peach syrup follows the same logic applied to thyme in the Blueberry Lemon Thyme Spritzer and the Peach White Tea Spritzer: thyme's primary pleasant aromatic compounds — thymol at low concentrations and various terpene esters — extract at gentle temperatures ahead of the harsher, more camphor-adjacent compounds that develop with extended heat or prolonged infusion. Eight to ten minutes in the declining-temperature post-simmer produces a background herbal warmth that lifts and complexifies the peach's sweetness. Remove and discard all thyme sprigs at the 10-minute mark without exception.

Strain the peach thyme syrup through a fine-mesh sieve into a clean jug, pressing gently on the mashed peach solids to extract the liquid. Press gently rather than aggressively — the goal is a clean, slightly thick, amber-coloured syrup rather than a cloudy, pulp-present juice; forceful pressing produces the latter. Discard the strained solids. Allow the peach thyme syrup to cool completely. Once both the white tea base and the peach thyme syrup are cold, combine them in a large pitcher. Stir in 45ml of fresh lemon juice. Taste and assess: the combined drink should be specifically peach-forward with a background herbal warmth from the thyme, light floral bitterness from the white tea, and the clean acid brightness from the lemon sharpening the overall flavour profile. If the brightness is insufficient, add additional lemon juice up to 60ml total. If the peaches were under-ripe and the syrup is not sufficiently sweet, add a small splash of honey or a teaspoon of granulated sugar dissolved in a small amount of warm water.

Fill four glasses generously with ice cubes — large cubes specifically preferred to slow dilution, as this iced tea is served still rather than with carbonation and the melting ice is the primary dilution mechanism. Pour the peach thyme iced tea over the ice. The tea is served still rather than sparkling — the format specifically chosen for the iced tea rather than spritzer preparation, where the tea's light tannic structure and the peach's delicate aromatics are best presented without the carbonation's interference. Garnish each glass with 2–3 thin peach slices — cut immediately before serving to prevent browning. Add a small thyme sprig resting across the ice. Serve immediately while cold, aromatic, lightly tannic, and specifically peach-forward.