Preheat your oven to 180°C (350°F). Spread the hazelnuts on a baking sheet and toast for 10-12 minutes until fragrant and golden. Shake the pan halfway through for even toasting, then let cool slightly.
Chop the toasted hazelnuts coarsely and set aside about 1/4 cup for topping later. Mix the remaining hazelnuts in a bowl with the pitted dates and vanilla extract until well combined and sticky.
In a small saucepan over low heat, melt the coconut oil and stir in the chocolate chips. Continue stirring until smooth and melted, then remove from heat.
Pour the melted chocolate mixture into the bowl with the hazelnut-date mixture. Add a pinch of sea salt and stir until everything is evenly coated and sticky.
Line the baking dish with parchment paper and transfer the mixture into it. Use the back of a spatula or your fingers to press the mixture firmly into an even layer.
Sprinkle the reserved chopped hazelnuts evenly over the top and gently press them into the surface for added crunch and decoration.
Place the dish in the refrigerator and chill for at least 2 hours until the mixture is firm and slices cleanly. For quicker setting, freeze for about 1 hour.
Once set, lift the block out of the dish using the parchment paper and transfer to a cutting board. Use a sharp knife dipped in hot water to slice into 12 equal squares.
Serve the hazelnut bites chilled, enjoying the crunchy exterior and gooey, nutty interior with every bite.
