Prepare the Cookie Dough

1. Preheat Oven: Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper or a silicone mat.
2. Mix Dry Ingredients: In a medium bowl, whisk together the flour, baking soda, salt, instant coffee, and cocoa powder. Set aside.
3. Cream Butter and Sugars: In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy.
4. Add the Egg and Vanilla: Beat in the egg and vanilla extract until fully combined.
5. Combine the Wet and Dry Ingredients: Gradually add the dry ingredients to the wet mixture, mixing until just combined. Be careful not to overmix.
6. Fold in Chocolate Chips: If using chocolate chips, fold them into the dough. You can also add any other mix-ins you like, such as nuts or toffee bits.

Shape the Cookies

1. Scoop the Dough: Use a tablespoon or cookie scoop to scoop the dough onto the prepared baking sheets. Space the cookies about 2 inches apart.
2. Flatten the Dough: Gently press down on the dough balls to flatten them slightly. This will help the cookies bake more evenly.
3. Bake: Bake in the preheated oven for 12-15 minutes, or until the edges are set and the centers are slightly soft. The cookies will continue to firm up as they cool.
4. Cool: Remove from the oven and let the cookies cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.

Make the Mocha Drizzle (Optional)

1. Melt the Chocolate: In a microwave-safe bowl, combine the heavy cream, semisweet chocolate chips, and instant coffee granules (if using). Microwave in 20-second intervals, stirring in between, until the chocolate is completely melted and smooth.
2. Drizzle the Mocha Mixture: Drizzle the melted mocha mixture over the cooled cookies using a spoon or a piping bag for more control.