Make the Salted Caramel Sauce: Make the Salted Caramel Sauce before you start everything else, so it has time to chill and set up a bit. It takes just 10 minutes! This can be made up to 1 week in advance - store in the fridge in a jar. 1 cup granulated sugar , 6 tbsp salted butter, cubed, 1/2 cup + 1 tbsp heavy cream, pinch of flaky sea salt
Make the Crust: In a medium bowl, whisk together the flour, salt, and sugar. Cut the butter into large chunks and add to the dry ingredients. Use a pastry cutter or clean hands to cut the butter into the dry ingredients until you have chunks the size of blueberries (some will be a bit bigger, and some a bit smaller). Drizzle in the water and add the sour cream. Toss with a fork until the dough is moistened and the sour cream is mixed in. Gently gather the dough into a ball. If the dough holds when you push it together, it's ready. If it's a bit dry and crumbles apart, add a bit more water, 1 to 2 tablespoons at a time. You can also flick some water onto any dry bits hiding in the bottom of the bowl. Gently flatten the ball of dough a bit, into a 1-inch thick disc. It will be a little scrappy looking but should hold together. Wrap the disc tightly in plastic wrap and chill in the freezer for at leas 1 hour or in the fridge for at least 2 hours. If you freeze the dough for 1 hour, and your filling isn't ready yet, move the dough to the fridge so it doesn't freeze solid. Make-Ahead Tip: Dough can be made ahead and refrigerated for 2-3 days before using, or frozen for up to two months. Let it thaw in the fridge overnight before using, if you froze it. Find More Troubleshooting Tips for Pie Crust in my "How to Make Perfect Pie Crust" Post. 1 and 1/4 cups all-purpose flour, spooned & leveled or weighed out , 3/4 tsp salt, 1 tsp granulated sugar, 1/2 cup cold salted butter, 5 tbsp ice-cold water, 1/4 cup cold, full-fat sour cream
Make the Apple Filling: Start the filling once the dough has chilled, or while it's close to being ready. If you're making the filling the same day that you made the crust, you can use the same bowl. Just give it a quick wipe first! Peel and slice your apples 1/4" thick. You'll have about 4 cups of slices. Stir together the apple slices and the rest of the filling ingredients. If the dough still has a few minutes of chill time left, you can cover the bowl of apple filling with a kitchen towel and pop it in the fridge while you wait and while you roll out the dough. 3 medium apples , 2 tsp lemon juice, 1 and 1/2 tbsp all-purpose flour, 1/4 cup brown sugar, packed, 1 tsp vanilla extract, 1 and 1/4 tsp cinnamon, 1/4 tsp nutmeg, 1/8 tsp ground cloves, 1/4 tsp salt
Roll out the Dough and Assemble the Galette: Preheat oven to 400° F, and line a large baking sheet with parchment paper or a silicone baking mat. Flour your countertop & rolling pin. Unwrap the dough and sprinkle lightly with flour. Begin rolling out the dough gently, turning continuously so it doesn't stick to the counter. Sprinkle more flour under the dough as needed. Be a little patient here - we're not trying to stretch the dough all the way out in a few passes. Once the dough is about 12 to 14 inches in diameter and about 1/8 inch thick, gently roll it up onto the rolling pin and transfer it onto the prepared baking sheet. Evenly spread the apple filling onto the dough, leaving a 2- to 3-inch border around the edges. You can fan the apple slices out in circles or you can let them fall where they fall. Just try to keep them in an even layer throughout. Drizzle the little bit of liquid left in the bottom of the bowl over the apple slices. Fold up the edges of the dough, working in small sections, to cover edges of the apples. Galettes are rustic - don't fuss over this. Chill the assembled galette, uncovered, in the fridge for 15 minutes to re-chill before baking (don't skip this). Beat the egg in an already used measuring cup. Once the galette has chilled, brush the beaten egg (your egg wash) over the edges of the crust. Sprinkle on coarse sugar. 1 large egg, for egg wash, sprinkle of raw or turbinado sugar, for garnishing crust
Bake: Bake for 38 to 45 minutes. The crust will be golden brown and should feel crisp if you tap it with your fingertip. You can also prick the apples with a fork to ensure they're tender.
Serve + Store: Brush the apple slices in the galette with salted caramel sauce when it comes out of the oven. If the caramel has been in the fridge awhile, you'll need to microwave it for 30 sec to 1 minute to loosen it up. Let the galette rest about 10 minutes before slicing + serving. Drizzle slices with more salted caramel sauce, and serve with vanilla ice cream. This is best fresh from the oven, but you can keep leftovers in the fridge for 2-3 days in an airtight container.