Helen's Peanut Butter Cookies -Grandma

2 cups brown sugar
2 cups white sugar
4 eggs
2 cups shortening
2 tsp. vanilla
4 tsp. baking soda
1 tsp. salt
5 cups flour
2 cups peanut butter

Blend together sugars, eggs, shortening, and vanilla. Sift together baking soda, salt, and flour, then combine the mixtures together. Mix in peanut butter and drop by spoonfuls onto pan. Mash gently with a fork and bake at 325° for 10-12 minutes.