Rinse and dry the strawberries, trim off the stems, then slice and chop the flesh into pieces about a quarter inch across. Keep the pieces small and fairly even so they soften together and pass through a wide straw.

Combine the chopped fruit and sugar in a skillet over medium heat, stirring with a spatula as the berries release their juice and the liquid reduces. Finish cooking when the mixture looks glossy and syrupy, with gentle bubbling and soft strawberry pieces still visible.

Take the skillet off the burner, spoon the compote into a storage container, close it, and refrigerate for at least two hours. The mixture should feel thoroughly cold and remain spoonable before you assemble the drinks.

Spoon chilled compote into the serving glasses, streak it along the inner walls with the back of the spoon, add optional ice, and gently pour in the whole milk before serving immediately. The fruit should form red ribbons against the white milk, turning pastel pink as you stir.