Vegan Spiced Plum Crumble

(c.2 cups) plain flour (aka all-purpose)

sea salt

(c.4½ oz) vegan butter or margarine

(c.½ cup) demerara sugar

(c.⅓ cup) white sugar

(c.2 oz) ground almonds

slivered almonds

(c.2 lbs) fresh plums, stones removed

demerara sugar

vanilla pod, seeds only

ground cinnamon

ground anise

ground nutmeg

ground cloves

ground cardamom