Prep: Preheat oven to 350℉. Line a 9x13 baking dish with parchment, ensuring there are some extra on each side over-hanging to assist with lifting out the bars. Spray with olive oil or your favorite non-stick cooking spray.
Make Crust: Combine crushed graham crackers and melted butter in a small mixing bowl. Pour out into the baking dish and spread out evenly. Press down firmly with hands to create a flat crust on the bottom.
1st Bake: Place in the oven, middle rack, for 10 minutes. Remove and let cool (feel free to pop in the fridge for 5-10 minutes to help it cool down quickly).
Layer: Spread out ½ cup walnuts, ½ cup milk chocolate candies, ⅓ cup peanut butter chips, ¼ cup mini dark chocolate chips, and 1-2 tablespoons rolled oats evenly across the graham cracker crust. Pour 11.25 ounces dairy-free sweetened condensed coconut milk over top evenly. Feel free to sprinkle a few extra candies, oats or chocolate chips over top.
2nd Bake: Place in oven, middle rack, for 15-20 minutes.
Cool + Serve: Remove and let cool completely before cutting into squares and serving.
Notes
Gluten-Free: simply make sure you are using certified gluten-free oats and gluten-free graham crackers.
Sweetened Condensed Milk: if you aren't concerned with keeping it dairy-free, you can simply use a can of regular sweetened condensed milk.
Storage: simply place them in an airtight container in the refrigerator for up to 1 week.
Freezer: cut them into individual bars, place them in a single layer or place parchment paper in between layers, and store in a freezer-safe container for up to 3 months.