6 ounces (1 1/2 sticks) unsalted butter
1 packed cup light brown sugar
1/2 cup granulated sugar
2 teaspoons vanilla extract
2 large eggs
2 1/4 cups all-purpose flour
1 teaspoon baking powder
1/2 teaspoon baking soda
1 cup semisweet chocolate morsels
1 cup salted peanuts
Using a microwave oven or in a small saucepan, melt butter. Allow it to cool for about 5 minutes. In a medium bowl, using an electric mixer or by hand, beat together the butter, brown sugar, and granulated sugar. Beat in vanilla, eggs, flour, baking powder and baking soda. Fold in chocolate morsels and peanuts.
Refrigerate bowl of cookie dough for 20 minutes. Meanwhile, heat oven to 350 degrees. Line a large baking sheet (or two) with a nonstick liner or parchment paper.
Shape chilled dough into fat disks about 2 1/2 inches in diameter and 1/2-inch thick (slightly less than 3 tablespoons of dough for each cookie). Place cookies on baking sheet 1 1/2 inches apart. Bake until golden brown around edges and cracked and chewy in middle, about 15 minutes. If using two sheets, switch position of sheets halfway through baking. Remove cookies from oven while they are still soft in center or they will lose their chewiness as they cool.
Allow cookies to rest on baking sheets for about 3 minutes before transferring them to wire racks to cool. When completely cool, store in an airtight container.
Yield: About 20 cookies.