1. Add the butter to a small saucepan and melt. Let cook over medium-high heat for several minutes until the butter smells nutty, and you can see brown spots on the bottom of the saucepan. Remove from the heat, let cool down for 2-3 minutes, then add the cocoa powder and chopped chocolate and mix to combine until the chocolate has melted completely. Set aside and let cool down a bit further.

2. Preheat the oven to 325°F (160°C). Line a square 8×8 inches (20x20cm) baking pan with baking parchment and set aside. Chop the second batch of chocolate and set aside.

3. In a large bowl mix the eggs with both sugars for about 3-4 minutes on high until very light and fluffy. Add the oil, vanilla extract, and cooled chocolate sauce – mix until well combined. Mix the flour with instant espresso powder, ground cardamom, and salt and add to the bowl. Mix only shortly until just combined. Add the chopped chocolate and fold in.

4. Pour the batter into the prepared pan and spread evenly. Place the cookies on top of the batter and sprinkle with some flaky sea salt. Bake the brownies for about 45-48 minutes. Take out of the oven and let cool down completely. Cut into 9 squares before serving.