Cream the butter and sugar, add the egg yolk, then slowly add the orange juice.
Slowly add in the flour until combined.
Wrap in plastic wrap and refrigerate for at least one hour.
Preheat the oven to 375 degrees F.
Measure out dough in level teaspoons to ensure uniform sizing. Roll balls in your hands to smooth, place on cookie sheet.
Use your thumb or pointing finger to gently press the center of the cookie, forming an indent. Bake for 10 minutes.
Remove from oven, fill indents with preserves, lemon or lime curd, marmalade, or even apple butter. Return to oven and bake 5-6 minutes more, do not let them get brown.
Cool on wire racks. Sprinkle with powdered sugar if desired.
These cookies are SMALL - hence using a TEASPOON to make the dough ball. You can make them bigger by using a tablespoon or regular sized cookie scoop and you will get about 45 cookies.
Use your thumb or pointing finger to gently press the center of the cookie, forming an indent. Pressing the cookie will cause it to lean to one side. After creating all the indents, I turn the cookie sheet around and repress each indent from the other side. This makes then stand back upright.
I like to use several different flavors of jam or preserves. My favorites are filled with lemon curd, but seedless blackberry preserves runs a very close second.