Every Christmas for I don't know how many years I've been baking jelly cookies for my kids. Both of them would probably say these are their favorite Christmas cookies. My son even insisted I bring them to his first grade class's Christmas party. Interesting party, as the kids--aside from my son--had never eaten a jelly cookie and thus wouldn't touch them; not a problem, for my son and the adults present ate them all. Because they are so good, I've decided that they should be made more often during the year, so I'm using a heart-shaped cutter and making them for Valentine's Day. When I make these for Christmas, I use a one-inch round cookie cutter, but my heart-shaped cookie cutter is slightly bigger, about 1 3/4 inches across and one inch vertically down the center of the heart. Just use the smallest heart you can find, or use a one-inch round cutter. Before investing in King Arthur cookie cutters of varying sizes, I used to use the cap off a bottle of Gerber baby juice. I'm not really sure how many dozen cookies this recipe makes, as I've never counted, but I'm estimating about six dozen.
1 cup softened butter (2 sticks)
1/2 cup sugar
2 egg yolks
1 1/2 tsp. vanilla
2 1/4 cups flour
1/2 cup seedless raspberry jam
Preheat oven to 300°. Beat butter, sugar, egg yolks, and vanilla until light and fluffy. Stir in flour to make a stiff dough. Roll dough out one quarter at a time to 1/4 inch. Cut with a one-inch cookie cutter. Place one inch apart on ungreased cookie sheets. Press center of each cookie with your fingertip. Spoon 1/4 teaspoon of jam into the hollow. Bake at 300° for 18 minutes until edges just begin to brown. Cool on wire racks. If any cookies are left after the first day, store in covered containers.