Chocolate Ganache Brownies

Preheat your oven to 180℃ (350℉).
Prepare a baking tin — for cakey and fudgy brownies, choose a pan that’s roughly 7.5 inches square. For thinner and gooey brownies, try a tin that’s roughly 7.5 x 12.5 inches (a classic brownie pan). Line with baking/parchment paper.
In a large heatproof bowl, add 200 g dark chocolate (chopped) and 60 ml olive oil. Bring a small saucepan of water to a boil and place the chocolate bowl over the saucepan. Melt. You can also use a microwave, but this method is easier to control.
In the same large bowl as the chocolate and olive oil, add 2 eggs Beat or whisk into the batter. Once thick, add 2 teaspoons vanilla extract and 50 g granulated sugar, whisking once again to combine.
Sift in the dry ingredients, including 35 g self-raising flour, 1 pinch baking powder, and 2 teaspoons cocoa powder. Fold into the batter until just mixed — don't overwork.
Once the oven comes to temperature, pour the brownie batter into your baking tin.
Bake on the middle shelf for around 25 minutes.
Make the chocolate ganache. Finely chop 100 g dark chocolate and place it in a heatproof medium bowl. In a small saucepan, heat 100 ml double cream until just bubbling. Pour the cream over the chopped chocolate and stir to combine; it should turn thick and glossy.
Finish the brownies by pouring the chocolate ganache over the top. Top with flaked sea salt and leave to set, then cut.