Note: If fermenting biscuit topping overnight, remove from the refrigerator at this time to soften while you prepare apple filling.
Wash your apples and peel all of the skins. Chop into 1/8 inch slices, and transfer to a medium-sized mixing bowl. Add the lemon juice to the apples and toss well. This keeps the apples fresh!
6 (about 750g) Granny Smith apples, 3 tbsp (45g) lemon juice
Add the flour, white sugar, brown sugar, cinnamon, cardamom, vanilla, salt and cream to the bowl. Mix well to combine all the ingredients.
½ cup (100g) white sugar, ⅓ cup (70g) brown sugar, 2 tsp cinnamon, 1 tsp cardamom, 1 tsp vanilla extract, ¼ tsp sea salt, 1 tbsp (15g) all-purpose flour, 3 tbsp (45g) heavy cream
In a large saucepan or 9-inch cast iron skillet on medium heat, add the butter. When butter has melted fully in the pan, add the apple filling to the pan. Cook on medium heat for 10-12 minutes, making sure to lift the apples off of the bottom of the pan to avoid burning. Apple filling should go from runny to thickened and caramelized. You should be able to stick a fork in the apples and feel some firmness, but they shouldn't be hard.
¼ cup (57g) unsalted butter
Remove filling from heat.