Preheat your oven to 350F. Line two large baking sheets with parchment paper and set aside.

In a mixing bowl, using a stand mixer or handheld electric mixer, blend the butter and sugars until the mixture is completely creamy, around 1-2 minutes. Add in the peanut butter, egg, and vanilla, and mix until smooth.

In a separate bowl, mix together the flour, baking soda, cinnamon, and salt. Gradually combine the flour mixture with the butter mixture to form a soft dough. Gently fold in the Rice Krispies cereal and chocolate chips.

Form the dough into 1-inch balls and place them 1 inch apart on the prepared baking sheets. Bake the cookies at 350F for 9 minutes, then take them out of the oven and tap the baking sheet on the counter a few times to flatten the cookies. Put the cookies back in the oven for an additional 3-4 minutes until the edges are lightly browned.

If desired, sprinkle a bit of flaky sea salt on top of the cookies. Let the cookies cool on the baking sheet for 10 minutes, then transfer them to a wire cooling rack to cool completely. Enjoy!