10 tablespoons unsalted butter plus more for greasing ramekins
3 cups granulated sugar plus more for dusting ramekins
16 oz. bittersweet chocolate
4 oz. unsweetened chocolate
4 tablespoons cornstarch
3 large eggs
4 egg yolks
4 teaspoons Grand Marnier
Powdered sugar, for dusting
Prepare your 12-4 oz. ramekins by buttering them heavily, making sure to get the corners. Roll granulated sugar in the ramekins to coat, tapping out any excess.
For the cake, use chocolate bars, not chips. The chips have extra ingredients in them to stop them from sticking together. Chop the chocolate finely, and cut the butter into small chickpea-sized nuggets.Put the butter and chocolate into a metal bowl that will fit snugly over a saucepan filled halfway up with water. Bring the water to a simmer and place bowl filled with chocolate and butter on top. Stir to melt and combine the chocolate and butter. Stir together until smooth and uniformIn a large bowl, combine the flour and cornstarch and mix well.
In a separate small bowl, combine the eggs, egg yolks, and grand marnier and beat the eggs until well scrambled.Add the melted chocolate/butter mix to the bowl with the flour/cornstarch and stir to combine. Add the egg mix and stir to combine well. Keep stirring until you have a deep dark mostly uniform mixture.
Scoop out about 1/2 cup of the batter into each ramekin. You may have to adjust the amounts as you get to the last ramekins.At this stage you may cover these with plastic and store for 24 hours before baking.
When you want to bake them, preheat an oven to 375 F. Place the ramekins in the oven and bake until the tops have set and show cracks - about 15-20 minutes. Don't overcook. You want a liquidy center.
Remove the ramekins and set them on a cooling rack for 2-3 minutes. To unmold, first run a knife between the cake and the ramekin walls to loosen. The ramekins will still be hot. Use a glove and grip the ramekin. Turn the ramekin over quickly just to set the chocolate lava cake off-center on the serving dish and dust with powdered sugar.