Preheat your oven to 400 F.
Prep the ramekins by rubbing butter on the insides or using a pastry brush to lightly but evenly spread oil on the insides. Then place a spoonful of flour or cocoa in your ramekin, shake it around to coat evenly and tap the excess out - ensure that there are no 'empty' patches especially in the inner edges. Place them on a baking sheet.
Melt the chocolate and butter together on low heat over a stove or in 30 second increments in a microwave until just melted, stir smooth and set aside.
In a mixer (or by hand) whisk your egg and yolks together till foamy and well combined, about a minute with an electric mixer.
Add the sugar and beat for two minutes at which point it'll look thicker and lighter.
Gently stir in (by hand using a spatula) your cocoa powder, flour, salt and then finally the chocolate. Be sure to scrape the sides and bottom of your bowl.
Divide your batter among your prepared ramekins, place back on the baking sheet and bake until the edges are puffy and set, the middle should not be. This usually takes me about 10 minutes, but please do check on it around 8. Depending on your chocolate it can take up to 12 minutes.
Remove from the oven, let sit for a minute, then carefully run a butter knife along the sides to make sure nothing has stuck and invert it on to your plate. Serve with vanilla ice cream. Or as is.