Preheat the oven to 170°C fan and line a 450g/1lb loaf tin
Mix the ground flax with 65ml of milk and leave to thicken
In a large bowl, mix the banana, yoghurt, grated carrot, flax mixture, maple syrup, vanilla, spices and salt
Fold in the wholemeal flour, oats, bicarbonate of soda and baking powder. Add remaining 15ml milk if needed - the batter should be thick and spoonable
Fold through the raisins and 50g walnuts
Spoon into the tin and scatter the remaining 20g walnuts on top
Bake for 55–65 minutes, until deeply golden and set through the centre (cover loosely with foil if browning too quickly)
Cool fully before slicing, then freeze in slices or eat immediately
Serve warm with toppings and a generous spread of Philadelphia Protein cream cheese
