Place an oven rack in the middle position and preheat to 425°F (218°C).
Liberally grease four 6 oz ramekins with butter; ensure the sides and bottoms are completely covered. Add a teaspoon or two of cocoa powder into each ramekin. Rotate and gently tap the ramekins to get the cocoa powder to completely coat the inside surfaces. Place coated ramekins onto a rimmed baking sheet.
Fill a medium saucepan with about 2 inches of water and bring to a boil. Reduce heat to low.
In a medium, heatproof bowl, combine the chopped chocolate and cubed butter. Place the bowl over the just-simmering water and ensure that the bottom of the bowl is not touching the water.
With a heatproof spatula, gently stir the chocolate mixture until butter is melted and chocolate is almost completely melted. Remove from heat, wiping the condensation from the bottom of the bowl with a kitchen towel. Stir chocolate mixture until it is completely smooth (see Chef’s Tips).
Stir in the vanilla extract.
In a large bowl, using a hand mixer, whip eggs and salt until foamy; 1 minute.
With the mixer on medium speed, slowly add in the Redpath® Dark Brown Sugar, about a tablespoon or so at a time. After each addition, increase speed to high and beat until well incorporated and return to medium speed. Repeat process with the remaining brown sugar. When all of the brown sugar is incorporated, increase speed to high and beat for 5 minutes until thickened and pale in colour.
Transfer the egg mixture into the bowl of melted chocolate. Sift the flour over the surface of the egg mixture. With a large rubber spatula, gently fold the mixture together until just combined.
Evenly divide the batter into the prepared ramekins (see Chef’s Tips). Place the baking sheet into the preheated oven and bake until the sides are set, the cakes have puffed slightly, and the centres still have a slight wobble when gently shaken; 9 to 11 minutes.
Allow cakes to cool for about a minute. Gently run a small offset spatula around the rim of each cake.
Place a small plate over the ramekin and, with the help of an oven mitt or kitchen towel, gently turn the plate and ramekin over. Wait a few seconds to allow the cake to drop away from the ramekin before carefully lifting the ramekin off of the cake. Repeat process with the remaining cakes.
Dust the cake tops with Redpath® Icing sugar or cocoa powder if desired. Garnish with fruit, shredded coconut, and/or whipped cream. Serve immediately.