from one of the best recipe books "The Gourmet Cookbook" Ruth Reichl
page 674
1 Cup creamy or chunky peanut butter
1 Cup sugar
1 large egg, lightly beaten
1 teaspoon baking soda
Put a rack in middle of oven and preheat oven to 350 degrees. Lightly butter two large baking sheets. Beat together peanut butter and sugar in a medium bowl with an electric mixer at medium speed until well combined, about 2 minutes. Beat in egg and baking soda until well combined.
Roll level teaspoons of dough into balls and arrange about 1 inch apart on buttered baking sheets. Flatten balls with tines of fork, making a crosshatch pattern, to 1 1/2 inch rounds.
Bake cookies in batches until puffed and pale golden, about 10 minutes per batch. Cool on baking sheets for 2 minutes, then transfer to racks to cool.THE BEST