These little tarts or cookies are my sons’ absolute agreed favorite. I used to send home baked cookies into my eldest son’s 2nd grade class every Monday and these were requested over and over by all of the children.
Banbury Tarts:
3 sticks of butter (I highly recommend not substituting)
1 cup sugar
1 egg
1 tsp pure vanilla extract
4 cups flour
jam of your choice (we like strawberry, raspberry, and blackberry)
Cream butter and sugar. 
Add the egg and vanilla. Add the flour and mix until just incorporated (if you beat to death, it will be tough). Form the dough into little balls and indent the tops with your thumb. 
Spoon jam into indentations. Bake 350 degrees for 10 minutes. Let cool before eating, as jam will be really hot when it comes out of the oven.
Yummy! I’m not much of baker so I won’t be playing along often unfortunately. I’ll be checking out all your good stuff though 🙂
YUMMY! Grams just always called these thumbprint cookies – nice to know the real name!