Preheat your oven to 325°F.
In a medium bowl, combine the graham cracker crumbs, melted butter, and 1/4 cup sugar. Mix until well combined.
Press the mixture firmly into the bottom of a 9-inch springform pan to form the crust.
Bake for 10 minutes, then remove from the oven and let cool.
In a large mixing bowl, beat the softened cream cheese with 1/2 cup sugar and vanilla extract until smooth and creamy.
Add the eggs one at a time, mixing well after each addition.
Stir in the sour cream, rolled oats, cinnamon, and salt until fully combined.
Pour the cheesecake batter over the cooled crust in the springform pan.
Sprinkle the mini marshmallows and chocolate chips evenly on top.
Bake for 50-60 minutes, or until the center is set but still slightly jiggly.
Turn off the oven and crack the door, allowing the cheesecake to cool in the oven for 1 hour.
After cooling, refrigerate the cheesecake for at least 4 hours or overnight for best results.
Before serving, slice into wedges and enjoy!