Mix together the butter, honey, egg and milk in a jug. Put the banana, flour, oats, baking powder and ground and flaked almonds in a large bowl. Pour in the milk mixture and quickly mix together all the ingredients to give a fairly lumpy mixture (this will give the muffins their lightness).
Line a 12-section muffin tin with paper cases and spoon in the batter. Bake in a preheated oven, 200°C (400°F), Gas Mark 6, for about 20 minutes until golden. Serve with butter and honey. Leftover muffins can be frozen or stored in an airtight container for three days.