Ingredients for 1 servings:
1. 3/4 cup unsalted butter (softened)
2. 1 cup firmly packed brown sugar
3. 1/4 cup white sugar
4. 1 large egg (take 30 minutes to bring it to room temperature first)
5. 2 teaspoons pure vanilla extract
6. 2 cups all-purpose flour
7. 2 teaspoons cornstarch
8. 1 teaspoon baking soda
9. 1/2 teaspoon salt
10. 8 ounces bittersweet chocolate, cut into small chunks

Directions:
1. In a large mixing bowl, cream together butter and sugars until smooth (I do this by hand, with a wooden spoon).
2. Stir in vanilla and then blend in egg.
3. Add the flour, cornstarch, baking soda and salt (I sift these four ingredients through a sieve first) and combine; stir in chocolate chunks and stir to incorporate chunks throughout the dough.
4. Chill dough in fridge for one hour, two if you can spare the time.
5. Preheat oven to 350°F; line your cookie sheets with parchment paper.
6. Drop dough by tablespoons onto cookie sheets and bake in preheated oven for about 8-10 minutes, or until cookies are golden brown around the edges.
7. Remove cookies to wire racks and let cool.