Preheat your oven to 350°F (175°C) and line an 8x8-inch baking dish with parchment paper, leaving some overhang for easy removal.
In a large mixing bowl, combine the chopped mixed nuts and rolled oats.
In a food processor, blend the pitted dates, almond butter, honey (or maple syrup), vanilla extract, and 1/4 teaspoon of sea salt until smooth and well combined.
Pour the date mixture over the nut and oat mixture, and stir until everything is evenly coated.
Transfer the mixture to the prepared baking dish and press it down firmly with a spatula or your hands to create an even layer.
Bake in the preheated oven for about 20-25 minutes, or until the edges are golden brown.
Remove from the oven and let it cool in the pan for about 10 minutes. While still warm, sprinkle the dark chocolate chips on top and let them melt slightly before spreading them evenly over the bars.
Sprinkle the remaining teaspoon of sea salt on top of the melted chocolate.
Allow the bars to cool completely in the pan before lifting them out using the parchment overhang. Cut into squares or bars.