• Set your oven to 300°F (149°C). Grab an 8-inch square pan and prep it with parchment paper. Make sure you leave extra hanging over the sides. Set the pan aside.

Traditional Pie Crust

• In a medium bowl, mix melted butter, vanilla, sugar, and a teaspoon of salt. Once combined, stir in your flour until you've got a smooth, doughy mixture.
• Press the dough firmly into your prepared baking pan and cover the bottom evenly. Slide it into the preheated oven for a quick bake (about 15 minutes).

Apple Filling

• Choose a crisp variety (like Granny Smiths) and slice them thin. Toss these slices into a large bowl, then flour, cinnamon, sugar, and nutmeg. Stir everything together until these medium apples are coated. Set it aside.

Streusel

• In a separate bowl, combine oats, flour, brown sugar, and cinnamon. Grab your butter (it needs to be cold), cut it into small chunks, and then work it into the dry mixture until the texture turns crumbly. Set it aside.

Assemble and Serve

• Turn up the oven to 350°F (177°C). Pile the apple slices atop your warm crust (from Step 2) and press the apples down gently so they fit snugly. Sprinkle the streusel over the apples and make sure to cover every inch.
• Bake for about 30-35 minutes until your streusel turns golden brown. Take it out of the oven.
• Let it rest on the counter for about 20 minutes, then refrigerate it for a couple of hours to firm up. (If you can leave it overnight, even better.)
• Lift the whole dessert out of your baking pan and slice it into 16 small or 12 large squares. Drizzle each square with salted caramel sauce. Enjoy!