Preheat your oven to 180°C (350°F). Spread almonds evenly on a baking sheet and toast for 8-10 minutes, until fragrant and golden. Remove and let cool completely, then chop roughly.
In a heatproof bowl set over simmering water, melt the chopped dark chocolate until smooth and glossy, stirring gently. Remove from heat and set aside.
In a mixing bowl, beat the softened butter and powdered sugar together until creamy and light, about 2 minutes. Stir in the vanilla extract for added aroma.
Press the buttery mixture evenly into a parchment-lined 20x20 cm (8x8 inch) baking pan. Bake for 12-15 minutes until lightly golden, then allow to cool for 10 minutes.
Sprinkle the cooled, chopped almonds evenly over the crust, gently pressing them into the surface to ensure they stick.
Pour the melted chocolate over the almond layer, spreading it smoothly with a spatula to cover all the nuts completely. Sprinkle a pinch of sea salt on top for enhanced flavor.
Transfer the entire pan to the fridge and chill for at least 2 hours, or until the chocolate is firm and the bars are set.
Once set, lift the bars out of the pan using the parchment overhang. Use a sharp knife to cut into 12 even squares, wiping the blade between cuts for clean edges.
Serve immediately or store in an airtight container in the refrigerator for up to a week. For best presentation, let the bars sit at room temperature for 10 minutes before serving.
