Peel, core, and dice your apples to a size you like. I kept mine a bit on the larger side but it doesn't matter except for your preferred texture at the end.
2½ Cups Diced Apple
In a bowl, add the apples, cinnamon, salt, and white sugar, and mix until the apples are well coated. Set this aside for about 2-3 hours to prepare the apples.
1 Tsp Cinnamon, ¼ Tsp Salt, 2 Tsp White Sugar
Preheat your oven to 350℉. Grease your cake pan (I use a 9" pan) with some extra butter.
Spread the apples over the bottom of the pan and set it aside.
In another bowl, mix together the brown sugar, flour, baking powder, and baking soda. Add in the melted butter and buttermilk, and stir until it combines into a batter.
¾ Cup Butter, ¼ Cup Brown Sugar, ¾ Cup Buttermilk, 1½ Cups Flour, 1 Tsp Baking Soda, 1 Tsp Baking Powder
Spoon the batter over the apples and spread to cover evenly. It'll be thick for a cake batter, but that's fine.
Bake your cake for 25-30 minutes, until cooked through. Remove from the oven, let cool, and serve with ice cream, whipped cream, a drizzle of caramel, or whatever you like!