prepare the base: in a large mixing bowl, combine the brown rice cereal, runny peanut butter, vanilla extract, and maple syrup. stir well until all ingredients are evenly incorporated.

form the squares: transfer the mixture into a parchment paper-lined square baking dish, pressing it down firmly and evenly to create a smooth layer.

freeze the base: place the dish in the freezer and allow the mixture to firm up for about 2 hours, or until it's solidified.

prepare the chocolate topping:in a microwave-safe bowl, melt the chocolate chips and coconut oil together in short intervals, stirring frequently until smooth and fully melted.

add the chocolate topping:remove the baking dish from the freezer and pour the melted chocolate mixture evenly over the chilled peanut butter rice crisp base, spreading it out with a spatula to cover the entire surface.

freeze again:return the dish to the freezer and let it chill for another 1-2 hours, or until the chocolate layer is set.

cut into squares: once the chocolate layer has hardened, remove the dish from the freezer and lift the parchment paper to transfer the whole slab onto a cutting board. using a sharp knife, cut the chilled mixture into squares of your desired size.

garnish and serve: sprinkle a pinch of sea salt over the top of each square for an extra burst of flavor. serve immediately and store the squares in the freezer. thaw before eating and enjoy!