Peel the sweet potatoes and dice them into 1cm cubes.

Soak the diced sweet potatoes in cold water to remove starch.

Drain the sweet potatoes and pat them dry with paper towels.

Sprinkle a little cake flour over the sweet potatoes and mix well.

In a bowl, whip softened butter until creamy, then add sugar in two batches and mix well.

Add eggs one at a time, mixing thoroughly after each addition.

Sift the dry ingredients (cake flour and baking powder) into the bowl and mix until combined.

Fold in the sweet potatoes using a spatula.

Grease a pound cake tin with melted butter and fill it with batter up to 80% full.