1
Preheat the oven to 425°F (220°C).
2
Butter a 9-inch (23cm) round cake pan and dust it with flour.
3
Melt the chocolate in a double boiler or in the microwave in 30-second increments, stirring between each interval.
4
In a medium bowl, whisk together the flour, sugar, and salt.
5
In a large bowl, whisk together the eggs and vanilla extract.
6
Add the flour mixture to the egg mixture and whisk until just combined.
7
Pour in the melted chocolate and whisk until smooth.
8
Pour the batter into the prepared pan and smooth the top.
9
Bake for 25-30 minutes or until the edges are set and the center is still slightly jiggly.
10
Remove from the oven and let cool in the pan for 5 minutes.
11
Transfer to a wire rack to cool completely.