Preheat your oven to 325°F (160°C) and prepare a 9x9-inch baking pan by greasing or lining it with parchment paper.

Melt chopped white chocolate and unsalted butter in a double boiler over medium-low heat until smooth and glossy, about 5 to 7 minutes.

Whisk together the eggs, egg yolks, sugar, and vanilla extract in a separate bowl until pale and thick, around 3 minutes.

Slowly drizzle the melted chocolate-butter mixture into the egg mixture, stirring gently until fully combined.

Sift in flour and salt, folding gently until just incorporated; the batter should remain lumpy.

Pour the brownie batter into the prepared pan and smooth the top evenly with a spatula.

Bake for 29 to 33 minutes, checking doneness with a toothpick; it should come out with moist crumbs.

Let the brownies cool completely in the pan on a wire rack before cutting into squares.