Preheat the oven to 350ºF. Prepare a 8x8 pan by throughly greasing the pan. Line the bottom with parchment paper to prevent the brownies from getting stuck in the pan.

In a large heatproof bowl, add the cubed butter, chopped chocolate, and olive oil. Place the bowl over a saucepan that's been filled a quarter of the way with water. Cook over low heat until the butter and chocolate are completely melted, stirring occasionally.

Once the butter, chocolate, and oil mixture is smooth, remove from the heat and set aside to cool completely.

Using a stand mixer on high speed, whisk together the eggs, granulated sugar, light brown sugar, and vanilla. Whisk on high for 3-5 minutes, or until the mixture is double in size and pale. You're looking for a creamy consistency that has formed soft peaks.

Add the cooled chocolate mixture to the egg mixture and gently fold to incorporate. Be sure to move slowly and gently to avoid knocking out the air from the egg mixture.

Once the chocolate and egg mixtures have fully combined, sift the flour and cocoa powder over the mixture. Gently fold the dry ingredients into the wet ingredients until they are mostly incorporated.

Add the chopped white chocolate and milk chocolate. Gently fold the chocolates into the batter until evenly dispersed.

Pour the brownie batter into the prepared 8x8 pan. Bake for 30 minutes, or until a shiny crust has formed and the middle is almost set with just a slight wiggle when moved.

Remove the brownies from the oven and allow to cool for at least thirty minutes before cutting. Sprinkle with sea salt, top with some vanilla ice cream, and enjoy!