Grease 7 to 8 custard cups (6 oz) with butter and place them on a baking pan.
Preheat oven to 425 degrees F.
In a small saucepan, combine ¾ cup butter and chocolates. Heat on low until melted stirring to blend. Set aside.
In a large bowl, combine eggs, egg yolks, vanilla and sugar. Beat on high for 5 minutes using an electric mixer. Add ⅓ of the chocolate mixture and mix then add the remaining chocolate and the flour stirring to blend. Spoon about ½ cup batter and do not over fill. Bake for 12 minutes. Remove from oven and let cool on a wire rack for about 3 minutes. Loosen cake and invert onto a serving plate. Sift powdered sugar over the cake. Serve
Recipe by The Gluten Free at https://www.theglutenfree.com/gluten-free-lava-cake/