Preheat oven to 350°F. Lightly grease two 7-oz ramekins and place them in an 8x8 or 9x9 baking dish. Set aside.
Melt the butter and set it aside to cool slightly while you proceed with the recipe. With a hand mixer or stand mixer with the whisk attachment, beat egg and sugar on medium high speed for 3 minutes, until thickened slightly and light yellow. Place a sieve over the mixing bowl and sift the cocoa powder, flour, and salt directly into the egg/sugar mixture. Mix on low speed until just combined, scraping the sides of the bowl as necessary. With the mixer still on low, slowly add in the melted butter and vanilla and mix again until just combined. Stir in the chocolate chips.
Divide the batter between the two ramekins and smooth the top. Pour hot tap water into the larger baking dish (that the ramekins are sitting in) the water should go almost halfway up the side of the ramekin (about and inch or two).
Carefully transfer the whole pan into the oven and bake for 45-50 minutes. The top should be set and puffed, with a slight jiggle in the very center. Cool slightly. Serve warm with vanilla ice cream and caramel sauce
