Line a twelve cup muffin pan with paper liners, or use cooking spray.
In a large bowl combine the flour, oats, baking powder, cinnamon, nutmeg and salt.
In a smaller bowl, whisk together the milk, egg, olive oil, maple syrup and vanilla.
Add the milk mixture to the flour mixture
Add the apple, dates, cranberries and walnuts
Stir just until dry ingredients are moistened
Spoon into prepared muffin pan cups
Bake in the centre of the oven for 20 minutes
Cool in the pan for five minutes before transferring the muffins to a rack to cool completely
Store at room temperature in an airtight container for up to 2 days
Omit the walnuts if anyone has a tree nut allergyTo make this recipe gluten-free, use a 1:1 gluten-free flour blend, and gluten-free rolled oats.To make the recipe dairy-free, use any non-dairy milkTry using an ice cream scoop to fill the muffin tin cups for evenly sized muffinsMost ovens are hotter towards the back, so it can be helpful to rotate your pan halfway through the baking time to ensure even baking.To freeze muffins, allow them to cool completely, then freeze them on a tray until firm. Transfer to a freezer-safe airtight container and freeze for up to a month. Alternatively, individually wrap each muffin before freezing.