Place one peach, sliced and pitted, and 8 ounces (250mL) of Highland Harvest Scotch Whisky in a sealed glass container. Infuse at room temperature for seven days. Once the infusion is complete, pour two ounces of the peach infused whisky, half an ounce of whole milk, the white of one egg, and a teaspoon of sugar in a mixer. Stir slowly until evenly mixed. Fill a tall glass with ice and pour in the contents of the mixer, then slowly top off with soda water while gently stirring until the glass is full and frothy. Garnish with a whisky-soaked peach slice from the infusion.