Pour the white and brown flours into a mixing bowl with three quarters of the oats and the butter, then rub in the butter with fingertips until the mixture forms fine crumbs. Add the honey, then beat the egg and milk together in a separate bowl. Gradually mix enough milk mixture into the butter and flour to make a soft, but not sticky, dough. Reserve the remaining milk mixture for glazing
Tip the dough out on to a lightly floured surface and knead very lightly until just smooth. Pat or roll into a rough shaped round about 20cm in diameter. Cut into eight wedge shapes then transfer to a buttered baking sheet, separating wedges slightly so that there is space for them to rise during baking.
Brush the tops with the remaining milk mix then sprinkle with the rest of the oats and sunflower seeds if using. Bake in a preheated oven set to 200°C/400°F/Gas 6 for 15-20 minutes until golden and well risen. Serve warm split and buttered.