My Favorite Peanut Butter Cookies

Ingredients
1/2 cup butter
1/2 cup peanut butter
1/2 cup sugar
1/2 cup brown sugar
1 egg
1/2 teaspoon vanilla
1 1/4 cups sifted flour
3/4 teaspoon baking soda
1/4 teaspoon salt

Instructions

Preheat oven to 375?. Mix first six ingredients.
Add the rest of the ingredients. Mix well.
Roll into balls and press down with a fork dipped in sugar or flour.
Bake for 12 to 15 minutes in the preheated oven, until just lightly browned.
Allow cookies to cool on baking sheet for 5 minutes before removing to a wire rack to cool completely.
Source : allrecipes.Com