Preheat oven to 350°F and position the oven rack in the middle position. Line 2-3 large baking sheets with parchment paper. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment, beat the granulated sugar, brown sugars, butter, and oil together. on medium speed for 3 minutes. Scrape down the sides after each minute. Add the egg and vanilla and beat another 1 minute. Again, scrape down the sides.
1 cup granulated sugar, ½ cup light brown sugar, ½ cup dark brown sugar, 1 cup unsalted butter, 1 cup canola oil, 1 large egg, 1½ teaspoons pure vanilla extract
While the sugar mixture is mixing, whisk the flour, salt, and baking soda together in a large bowl.
3½ cups all-purpose flour, 1½ teaspoons kosher salt, 1 teaspoon baking soda
Turn off the mixer and add the flour mixture. Turn the mixer to low and mix just until no flour is visible. Do not over-mix or the cookies won’t be as tender.
Add the Rice Krispies, oats, coconut, and ¾ of the chocolate chips and peanut butter chips. Mix just until incorporated.
1 cup Rice Krispies cereal, 1 cup old-fashioned rolled oats, ½ cup sweetened shredded coconut, 12 ounces milk chocolate chips, 11.5 ounces semi-sweet chocolate chips, 10 ounces peanut butter baking chips
At this point, the dough can be placed in an airtight container and refrigerated up to 2 days. If refrigerating, remove the dough from the fridge 1 hour prior to using.
When ready to bake, use a 2-inch diameter scoop (2 tablespoon size) to scoop the batter for each cookie. Place 2-3 inches apart on a baking sheet.
Top cookies with the remaining ¼ chocolate and peanut butter chips.
Bake 14-16 minutes, rotating the cookie sheet after 7 minutes.
Transfer cookies to a cooling rack and repeat the baking process until all cookies are baked.