Step 1

Line a cookie sheet with a silicone baking mat or parchment paper.

Step 2

Stir together melted butter with both sugars in a large bowl. Stir in egg yolk, vanilla, cocoa baking soda and salt. Slowly stir in flour. Stir in chocolate chips.

Step 3

Drop 2 tablespoon size cookie balls on prepared cookie sheet, 2-inches apart. Chill 30 minutes.

Step 4

Preheat oven to 350°F. Bake for 10-13 minutes or until just no longer glossy and lightly golden around the bottom edges. Cool before eating.

Step 5

Store in an airtight container for up to 3 days.