Prepare the Poaching Syrup: In a medium saucepan, combine the water, 1 cup sugar, and white wine (if using). Heat over medium heat, stirring until the sugar is completely dissolved. Bring to a gentle simmer.

Poach the Peaches: While the syrup simmers, carefully peel, halve, and pit the peaches. Gently place the peach halves into the simmering syrup. Reduce the heat to low, cover partially, and poach for 10-15 minutes, or until the peaches are tender when pierced with a fork but still hold their shape.

Cool the Peaches: Remove the saucepan from the heat. Stir in the vanilla extract. Allow the peaches to cool completely in the poaching liquid. Once cool, remove the peaches and set them aside. If desired, you can simmer the remaining liquid to reduce it slightly into a peach glaze.

Make the Raspberry Sauce: In a separate small saucepan, combine the raspberries, 1/4 cup sugar, and lemon juice. Cook over medium heat, stirring occasionally, until the berries break down and the sugar dissolves (about 5-7 minutes). Strain the mixture through a fine-mesh sieve to remove seeds, pressing down on the solids. Chill thoroughly.

Assemble the Melba: Place two peach halves in a chilled dessert bowl or coupe glass. Add a generous scoop of vanilla bean ice cream between or beside the peaches.

Serve immediately, generously drizzling the chilled raspberry sauce over the peaches and ice cream. Garnish with toasted slivered almonds.