Chocolate cookies

I love this simple chocolate cookie recipe from Martha Stewart.  They are perfectly crisp on the outside and chewy on the inside.  Normally, these cookies flatten out pretty well, but when I made them this time they stayed puffy.  I think it's because I used Silpats (silicone cookie sheet liners) instead of parchment paper.  I recently purchased a couple of them, and I'm still learning when to use them and when to not.  Flat or puffy, these cookies are tasty...enjoy!

Grammy's Chocolate Cookies (Martha Stewart)

2 cups all-purpose flour
3/4 cup Dutch cocoa powder
1 teaspoon baking soda
1/2 teaspoon salt
1 1/4 cups (2 sticks plus 4 tablespoons) unsalted, butter room temperature
2 cups sugar, plus more for dipping
2 large eggs
2 teaspoons pure vanilla extract

Sift together flour, cocoa powder, baking soda, and salt. Set aside.

In the bowl of an electric mixer fitted with the paddle attachment, beat butter, 2 cups sugar, and eggs on medium speed until light and fluffy, about 2 minutes. Add vanilla, and mix to combine. Gradually add dry ingredients, and combine with mixer on low speed. Cover bowl with plastic wrap, and chill until dough is firm, about 1 hour.

Preheat the oven to 350 degrees. Line baking sheets with Silpat baking mats. Roll dough into 1-inch balls. Dip top of each ball into sugar. Place on prepared baking sheets about 1 1/2 inches apart. Bake until set, about 8 minutes. Cool on baking sheets for 5 minutes before transferring to a wire rack to cool completely.