Grandma Mary'S Butter Cookies

Ingredients
- 1 c. sweet butter
- 1 c. granulated sugar
- 3 egg yolks
- 2 1/2 c. sifted flour
- 1 tsp. vanilla
Directions
- Cream butter.
- Beat into sugar.
- Add egg yolks and vanilla. Beat well after adding each yolk.
- Add flour and beat after each 1/2 cup is added.
- Chill about 1 hour.