In a large mixing bowl, stir together the dry ingredients for the base of the bars, including flour, quick oats, baking powder, cinnamon and salt. Next add in the melted vegan butter and maple syrup and stir everything well until a wet dough forms. Press the dough into your lined baking dish and set it aside.

To prepare the apple filling, thinly slice two large green apples and place them in a mixing bowl. Sprinkle over the flour, brown sugar and cinnamon and stir well until the apples have been well coated with the flour mixture. Set the apples aside while you prepare the crumb topping.

In another mixing bowl, stir together chopped pecans, flour, brown sugar and cinnamon until combined. Add in your solid vegan butter and using your hands or a spoon, cut the butter into the dry mixture until a batter like wet sand forms. Set it aside.

Now that you have all your components prepared, pour the sliced green apples onto the oatmeal base. Use your hands to spread them out into an even layer. Press them down slightly so they are compact.

Next, break up the wet, crumb topping as you sprinkle it overtop of the apples. Gently press the mixture down to get it to stick to the apples.

Bake the bars for 40 minutes or until set and golden brown on top.

Allow them to cool completely before using the parchment paper to carefully remove them from the pan and cut them into bars.