Line a 9x13-inch pan with parchment paper, leaving overhang on two sides. Mix graham cracker crumbs with melted butter, sugar, and cinnamon. Press firmly into the bottom using a measuring cup for even compression. Pre-bake the crust for 10 minutes at 325°F. Let cool completely while preparing the filling. This prevents soggy bottom in your caramel apple cheesecake bars.

Beat softened cream cheese for 2-3 minutes until completely smooth. Add sugar and beat until fluffy. Mix in eggs one at a time on low speed to prevent cracks. Add vanilla, sour cream, and flour just until combined. Pour over the cooled crust and spread evenly. Don't overmix or you'll incorporate too much air.

Dice apples into ½-inch pieces for even cooking. Sauté in butter with brown sugar, cinnamon, and nutmeg for 5-7 minutes. Add lemon juice to prevent browning and brighten flavor. Cook until slightly softened but still holding shape. Let cool for 5 minutes before spooning over cheesecake layer. Distribute evenly but don't worry about perfect placement.

Bake at 325°F for 45-50 minutes until center has slight jiggle. Turn off oven, crack door open, and let cool inside for 1 hour. Remove and cool at room temperature for another hour. Refrigerate for at least 4 hours, preferably overnight. Use parchment overhang to lift out before cutting. Should have golden crust, creamy center, and tender apples when your caramel apple cheesecake bars are done right.