Step 1

Heat oven to 350°F (177°C). Lightly butter a 10-ounce ramekin with ¼ tablespoon butter. Set aside.

Step 2

Place 2 tablespoons of butter in a small microwave safe bowl. Heat in microwave until just melted. Set aside.

Step 3

Whisk together the sugar, flour, and cocoa powder in a small bowl until thoroughly combined.

Step 4

Add the melted butter, egg yolk, and vanilla. Stir with a spoon or a rubber spatula to combine. Do not overmix.

Step 5

Fold in the chocolate chips.

Step 6

Pour the batter into the prepared ramekin. Spread into an even layer. Bake for 30 minutes.

Step 7

Remove from the oven and let cool for 5 minutes before enjoying. Top with ice cream, if desired.