Line your square dish with parchment paper, leaving some overhang for easy removal.
Place the dark chocolate in a microwave-safe bowl and melt it in 30-second bursts, stirring well after each, until smooth and glossy. This gentle melting keeps the chocolate silky and prevents burning.
Meanwhile, toast the chopped almonds in a dry skillet over medium heat, stirring frequently until fragrant and golden, about 3-4 minutes. Let them cool slightly—you’ll want that smoky aroma and crunch in your bars.
Add the butter to the melted chocolate and stir until smooth and shiny. The butter adds richness and a velvety texture to the mixture.
Fold in the toasted almonds and vanilla extract, mixing until evenly combined. The mixture will be thick and glossy, ready to set into bars.
Pour the mixture into your prepared dish and use a spatula to press it evenly into the corners, smoothing out the top for a clean finish.
Tap the dish lightly on the counter to remove any air bubbles and help the mixture settle. Chill in the fridge uncovered for at least 1 hour until fully set and firm.
Once set, lift the block out of the dish using the parchment overhang. Place on a cutting board and slice into 8 bars with a sharp knife, wiping the blade clean between cuts for neat edges.
Finish by sprinkling flaky sea salt or extra toasted almonds on top if you like a little extra flavor and crunch. Serve immediately or store in an airtight container in the fridge for up to a week.
