Gluten Free Chocolate Lava Cakes

unsalted butter (plus more for greasing)

dark or semi-sweet chocolate, chopped

eggs (100 g, weighed out of shell) + 2 egg yolks (50 g)

granulated sugar

pure vanilla extract

(26 g) all purpose gluten free flour blend (truly almost any finely ground flour blend will do, with or without xanthan gum)

unsweetened Dutch-processed cocoa powder

kosher salt

Confectioners’ sugar, for dusting (optional)