1. Add flour, sugar and salt to a large bowl and whisk to combine.
2. Using a box grater, shred/grate butter directly into flour. Butter doesn't need to be frozen, but make sure it's straight out of the fridge. Stick bowl in freezer for 10 minutes.
3. After 10 minutes, remove bowl and immediately use your fingers to break up the butter into the flour, smooshing (technical term) until butter is the size of small peas.
4. Add 3 tablespoons of water and mix to combine until dough comes together into a shaggy mess. Add more water 1 tablespoon at a time until everything comes together.
5. Dump dough onto a floured surface and knead until it becomes a more cohesive dough. Wrap in plastic wrap and let sit in the fridge for at least an hour, and up to overnight.
6. Preheat oven to 375. Line a large baking sheet with parchment paper.
7. In a large bowl, combine apples, maple syrup, cinnamon, cardamom and flour. Toss well to combine. Add sour cream and vanilla (if using) and mix to fully coat apples. Set aside while you roll out dough.
8. Take dough from fridge and set on a lightly floured workspace. Roll out to a 12-14 inch circle-thing (basically don't worry about it being a perfect circle), turning the dough 90 degrees after every few rolls. Carefully transfer dough to baking sheet.
9. Arrange apples on dough, leaving a 2-inch border around the edge. Gently fold that edge of dough up over the apples around the entire galette.
10. Brush dough with melted butter, drizzling the rest over the apples. Sprinkle dough with sugar.
11. Bake for 35-45 minutes, until apples are soft and crust is deeply brown. Ovens vary, so check often to see how it is doing.
12. Serve warm or at room temperature, with or without (or with) ice cream and/or whipped cream.

Recipe inspired and adapted from A Cozy Kitchen.