Preheat the oven to 350ºF. Prep a muffin tin by placing two thin strips of parchment paper in an x shape on the bottom of the mold. This will allow you to remove the mini pies from the pan easily.

Start by making the crumble. Add the crushed graham crackers, light brown sugar, and salt into a large mixing bowl. Mix until all of the ingredients are evenly dispersed.

Add the melted butter and vanilla and mix until all of the crumbs are evenly coated. Set aside.

Peel and dice the apples before adding to a large mixing bowl and tossing in lemon juice and vanilla.

In another small bowl, mix the brown sugar, cornstarch, and apple pie spice.

Add the sugar mixture to the apples and toss until evenly coated in the sugar mixture.

Line the muffin tin with the mini pie crusts, before adding the apple pie filling.

Add 25 grams of crumble on top of each pie by spooning it on top and gently pressing it into the filling until it is packed flat.

Cover the muffin tin with foil and bake for 25 minutes. The foil is important, as it prevents the top from burning while the filling fully bakes. Remove the foil and bake for another 5-10 minutes until the crumble is golden brown and crispy.

While the pies are still hot you can sprinkle with lemon zest for an extra kick. Serve with vanilla ice cream and enjoy!