Heat oven to 375�. In large bowl, combine sugar, brown sugar and margarine; beat until light and fluffy. Add peanut butter, vanilla and egg; blend well. Lightly spoon flour into measuring cup; level off. Add flour, baking soda and salt; mix well. Shape dough into 1 inch balls. Place 2 inches apart on ungreased cookie sheets. With fork dipped in sugar, flatten balls in crisscross pattern. Bake at 375� for 6 to 9 minutes or until golden brown and set. Immediately remove from cookie sheets. Yield 4 dozen cookies.

Variations: Chocolate Peanut Butter Crunch Bars: Prepare dough as directed. (Omit 4 t. sugar). Stir 1/2 cup crisp rice cereal into dough. Press in ungreased 15 x 10 inch baking pan. Bake at 350� for 12 to 17 minutes or until golden brown. Cool 15 minutes. Meanwhile, melt 1 cup semi-sweet chocolate chips and 1/2 cup peanut butter in medium saucepan over low heat. Stir in 1 1/2 cups crisp rice cereal. Spoon mixture evenly over slightly cooled bars; gently spread. Cool completely. Cut in bars. 48 bars.

Giant Peanut Butter Candy Cookies: Prepare dough as directed. Stir in 1 cup candy-coated chocolate pieces. Using 1/4 cup dough per cookie, place cookies 4 inches apart on ungreased cookie sheets. Flatten to 4 inch diameter. (Omit 4 t. sugar.) Bake at 350� for 8 to 12 minutes or until golden brown. Cool 1 minute; remove from cookie sheets. 14 cookies.

Oatmeal Peanut Butter Cookies: Prepare dough as directed, decreasing flour to 3/4 cup and adding 3/4 cup rolled oats. Cover dough with plastic wrap; refrigerate 2 hours for easier handling. Shape and flatten balls as directed. Bake at 375� for 6 to 10 minutes or until golden brown. 4 dozen cookies.

Peanut Butter and Jelly Thumbprints: Prepare dough and shape into balls as directed. Increase 4 t. sugar to 1/4 cup; roll balls in sugar. Place 1 inch apart on ungreased cookie sheets. With thumb, make deep imprint in center of each cookie. Bake as directed. Cool completely. Spoon 1/2 t. jelly, jam or preserves into imprint in each cookie. 4 dozen cookies.