In a food processor fitted with the blade attachment, combine the pitted dates, maple syrup, and cocoa powder. Blend until the mixture is thick and cohesive. Transfer the mixture to a medium mixing bowl. Add the chopped pecans and chocolate chips and stir with a rubber spatula just until combined.

Line an 8-inch/20 cm square baking dish with parchment paper. Press the mixture firmly into the dish using a flat spatula or your hands until even and compact. Freeze for 1½ hours, or until fully set.

Remove the slab from the freezer and place it on a cutting board. Using a sharp knife, slice into 12 equal bars.

Place the dark chocolate and coconut oil in a microwave-safe bowl. Microwave in 15-second intervals, stirring between each, until smooth and fully melted. Using a fork, dip each bar into the melted chocolate, letting the excess drip off. Place the bars on a parchment-lined baking sheet. If you prefer, drizzle the chocolate over the bars instead of coating them entirely.

Sprinkle with flaky sea salt, if using, and refrigerate until the chocolate sets. Store the bars in an airtight container in the refrigerator for up to one week.