Preheat oven to 200 degrees Celcius. Lightly grease a loaf pan and line with parchment paper. Allow a 2cm overhang on the long sides.
Sift flour, baking powder, salt and sugar in a large mixing bowl. Add butter and process until well-combined and mixture resembles fine breadcrumbs. Make a well in the centre.
Put strawberries, milk and egg in a food processor, and process until well-combined. Pour this into the well and stir with a palette knife until just combined. Turn out mixture onto a lightly floured tabletop. Knead lightly into a soft dough.
Roll out dough into a rectangular piece. Spread with strawberry jam over the dough. Brush the edge with a little milk. Roll up to enclose the jam.
Transfer the roll to prepared loaf pan with the seam side down, then cover with foil.
Bake for 20 minutes; remove the foil and brush the top with a little extra milk and continue to bake uncovered for 15-20 minutes or until golden and cooked through. Leave the loaf in the pan for 5-10 minutes. Cut loaf into slices and serve warm.