Preheat the oven to 350°F (175°C) and line two baking sheets with parchment paper.
Lightly crush 1 1/2 cups of Cinnamon Toast Crunch into a mixture of small pieces and crumbs. Set aside the additional cereal for topping.
In a medium bowl, whisk together the flour, baking soda, baking powder, salt, and cinnamon.
In a large mixing bowl, beat the softened butter, granulated sugar, and brown sugar for about 2 to 3 minutes, until creamy and slightly fluffy.
Add the eggs one at a time, mixing well after each addition. Beat in the vanilla extract.
Gradually add the dry ingredients to the wet mixture. Mix just until the flour is incorporated. Do not overmix.
Gently fold the crushed Cinnamon Toast Crunch into the dough.
Fold in the mini marshmallows, keeping most of them surrounded by the cookie dough.
Scoop the dough into portions and place them on the prepared baking sheets, leaving about 2 inches between each cookie.
Press a few reserved cereal pieces into the tops. If desired, lightly sprinkle with cinnamon sugar.
Bake for 9 to 12 minutes, or until the edges are lightly golden and set while the centers still look slightly soft.
Let the cookies cool on the baking sheet for about 5 minutes.
Transfer the cookies to a wire rack and allow them to cool for another 10 to 15 minutes before serving.
