Apple Snickerdoodle Bars

0 Preheat oven to 350°F (175°C). Line a 9x13-inch pan with parchment paper or spray the heck out of it with nonstick spray.
1 Mix dry ingredients: In a medium bowl, whisk together the flour, cream of tartar, baking soda, and salt. Set aside.
2 Whisk wet ingredients: In a large bowl, combine melted butter, brown sugar, and granulated sugar until smooth. Add eggs, vanilla, maple extract, and apple cider (if using). Whisk until it looks like it could be cookie dough batter’s moody sister.
3 Combine and fold: Stir the dry ingredients into the wet mixture until just combined. Fold in the chopped apples and toffee bits with a rubber spatula. Don’t overmix unless you want a dense brick of sadness.
4 Snickerdoodle the top: Spread the batter evenly into the pan. Mix the topping sugar and cinnamon, then sprinkle generously over the top like a snickerdoodle fairy.
5 Bake: 25–30 minutes or until the center is set and a toothpick comes out with a few moist crumbs (not raw batter). The edges will puff and pull slightly from the pan.
6 Cool and slice: Let cool completely in the pan for best slicing. Or go rogue and eat them warm with vanilla ice cream. I’m not your boss.