Mix together the water and honey. Heat a griddle pan. Brush the peach slices with the watered-down honey then griddle on each side until the slices have deep charred stripes. Put to one side while you griddle the baguette.
Drizzle the olive oil over the charred baguette slices. Divide the burrata between them and top each with half a slice of prosciutto and a griddled peach slice.