Whisk together all of the dry ingredients and set aside.
In another bowl, whisk together all of the wet ingredients.
Add the wet into the dry and stir to combine. You may need to knead the dough in order to fully incorporate the wet and the dry. Roll out the dough between two sheets of parchment paper, until it is about 1/8 inch thick. Remove the top sheet of parchment and cut the dough into squares, with a pizza wheel or a knife. Sprinkle the squares with a few shakes of pumpkin pie spice.
Transfer the dough (still attached to the bottom piece of parchment) onto a cookie sheet. Bake for 15 minutes.
Shut off the oven, crack the door and leave the cereal squares in the oven for 10-15 more minutes or until the squares are golden brown. Remove from the oven and allow to cook completely on the cookie sheet. Break apart the squares and store in a zip top bag or lidded container.