Line an 8x8-inch pan with parchment paper or foil, leaving an overhang on two opposite sides for easy removal; do not spray the pan. Set aside.

Place 1 cup packed pitted dates in a small blender jar or food processor and pulse until they form a very thick, sticky paste. If the dates are dry, soak them in warm water until softened, then drain and dry very well before processing.

Transfer the date paste to a large bowl. Microwave 1/3 cup creamy peanut butter and 1/3 cup pure maple syrup together for 15–20 seconds to loosen them, then add them to the date paste. Add 1 teaspoon vanilla extract and stir until evenly combined.

Stir in 1/2 cup quick 1-minute oats and 1 cup old-fashioned oats until incorporated.

Add 3/4 cup shelled and chopped pistachios and 1/2 cup miniature dark chocolate chips to the oat mixture. Mix thoroughly (use a spoon and then knead with clean hands if needed) until the nuts and mini chips are evenly distributed.

Press the mixture firmly and evenly into the prepared 8x8-inch pan using a spatula or the back of a spoon. Set the pan aside while you melt the topping chocolate.

In a large microwave-safe bowl combine 1 cup dark or milk chocolate chips and 2 teaspoons coconut oil. Microwave in 15-second increments, stirring between each increment, until the chocolate is fully melted and smooth.

Pour the melted chocolate over the pressed base and tilt/tilt-and-spread the pan so the chocolate forms an even layer across the top.

Cover the pan and refrigerate until the chocolate is set (about 30–60 minutes). Use the parchment or foil overhang to lift the slab from the pan, place on a cutting board, and cut into bars. If desired, warm a knife under hot water, dry it, and then use it to make cleaner cuts.