✓ Peel, core, and dice 2-3 medium apples into small cubes.

✓ In a medium bowl, combine the diced apples with salted butter, brown sugar, apple pie spice, and flour.

✓ Preheat oven to 400°F (205°C).

✓ In a large mixing bowl, combine the all-purpose flour, baking powder, baking soda, brown sugar, and melted salted butter.

✓ Stir in eggs, buttermilk, vanilla extract, and apple pie spice until just combined.

✓ Divide the dough into 8 equal portions. Roll each portion into a rope about 1-inch thick and 9-inches long, then cut into rings using a small ring cutter or by making a deep cross-cut in the center of the ropes.

✓ Spoon a generous amount of apple filling into the recessed center of each donut ring.

✓ In a separate bowl, mix white granulated sugar and cinnamon with 2 tablespoons of melted salted butter to create the topping.

✓ Brush the outer edge of each donut ring with some melted butter before dipping them in the sugar-cinnamon mixture.

✓ Place the coated and filled rings on a baking sheet lined with parchment paper. Bake at 400°F (205°C) for about 35 minutes or until golden brown.

✓ Remove from the oven, allow to cool slightly before serving.