Soak the bread crumbs in the milk until softened.

Add the finely chopped beef suet to the soaked bread crumbs and milk, and mix well to combine.

Butter a 5-cup pie dish or shallow baking dish thoroughly.

Place a layer of the bread crumb mixture on the bottom of the prepared dish.

Cover the bread crumb layer with a layer of blackberries, sliced apples, and sugar.

Continue layering the bread crumb mixture, blackberries, apples, and sugar, alternating layers and ensuring even distribution.

Finish with a thick layer of the bread crumb mixture on top.

Preheat oven to 375°F (190°C).

Bake in the preheated oven for approximately one hour, or until the pudding is golden brown and the fruit is tender.

Let cool slightly before serving.