Hot Chocolate Pudding Cake

From seasonsandsuppers.ca

1 stick unsalted butter, cubed
6 oz. semisweet or bittersweet chocolate, roughly chopped
3 large eggs, at room temperature
2/3 cup natural cane sugar
Pinch of sea salt

1. Preheat the oven to 375° degrees, with rack set in lower third of oven. Set ramekins or baking dishes on a baking sheet. No need to grease.
2. Put the butter and chocolate in a saucepan over very low heat. Stir until melted and smooth.
3. Whip the eggs, sugar, and salt until the mixture is light and foamy, and just holding its shape (like soft whipped cream). This should take about 5 minutes with an electric mixer, or longer if doing by hand. Fold one-third of the beaten eggs into the chocolate to lighten it, then scrape the lightened chocolate mixture over the beaten eggs, and fold it in just until there are no streaks of eggs visible.
4. Divide the batter into the baking dishes, filling them no more then 3/4 full (They will rise).
5. Bake the puddings for about 12 to 20 minutes (depending on size of baking dish) until the puddings are puffed up and the top is crusted and deeply cracked. A toothpick inserted into the centre will come out with some soft chocolate attached.