Pour Segura Viudas Rosé Cava into a large tupperware container with a lid. Seal and refrigerate overnight or for at least 7 hours, until Cava is frozen.
If you are using fresh strawberries, put them in a container and freeze overnight or for at least 7 hours.
Pour sugar and water in a small pan and heat until sugar has dissolved. Let cool to room temperature.
Add the frozen Cava, frozen strawberries, sugar syrup, and lemon in a blender, and blend until smooth.