Preheat the oven to 350. Line two baking sheets with silpat or parchment paper and set aside.

In a large bowl, mix together the flour, oats, cinnamon baking powder and salt until combined.

Make a well in the center and add egg, butter, honey, applesauce and vanilla. Mix the wet ingredients together in the well a little and then mix into the dry ingredients until just combined.

Fold in the chopped apple and walnuts, if using.

Spoon dough onto lined baking sheets in two even rows, about 8 cookies per baking sheet. These don't spread out very much while baking, so I sort-of arrange them and press them down into a cookie shape before baking.

Bake at 350 for 18-22 minutes, until golden brown.

Let cool completely. Store at room temperature for up to 3 days, in the fridge for up to 5 days or freeze for up to 5 months.