Preheat oven to 375 degrees. Cream together shortening and sugar. Blend in egg yolks and vanilla. Sift dry ingredients. Add peppermint extract. Mix well. Divide dough in half. Leave one half “as is”. Squeeze four or so drops of red food coloring into other half. Chill both halves. Roll walnut-sized balls into snake- shaped pieces. Twist one of each color together to make candy cane shape. Bake for 12 minutes on ungreased cookie sheet.