For the plums:
1 plum
2 teaspoons sugar
1 1/2 teaspoons lemon juice
1 1/2 teaspoons cornstarch
For the crumble topping:
1/4 cup flour
dash cinnamon
dash nutmeg
2 teaspoons sugar
1 tablespoon butter
Prepare the crumble topping:
In a bowl, stir together the flour and cornstarch, cinnamon, nutmeg and pinch of salt. Add the butter and sugar and start mixing everything together with your fingertips. You want to form a few large clusters of dough. It will be easier to grate once cold. Freeze the mixture while you prepare the fruit.
Preheat the oven at 350F and position a rack in the middle.
Prepare the plum:
In a bowl, combine the plum and the rest of the ingredients. Toss well. Spoon into a ramekin and place on a baking sheet as the fruit is most likely to release its juices, causing a spill. When ready to bake, grate the crumble over the ramekins (use a box grates) and bake for 30-35 minutes. Serve with whip cream or ice cream.