Place the oats, baking powder, spices, chopped apple and egg in a blender. Add most of the oat milk and blend until you have a thick, slightly textured batter.
Add more oat milk if needed—the mixture should be thick but pourable. If you have time, let it rest for about 10 minutes.
Stir in the chopped walnuts.
Heat a non-stick or heavy-based frying pan over medium heat and lightly grease with oil.
Spoon dollops of the batter into the pan and gently spread them into circles using the back of a spoon.
Cook for a couple of minutes, until the surface starts to set, then carefully flip and cook for another minute or so until golden.
Transfer to a plate and repeat with the remaining batter.
Serve warm with your favourite toppings—such as yogurt, fruit or a drizzle of maple syrup.