1 cup butter, room temp
3/4 cup sugar
In a large bowl, beat butter at medium speed until creamy, add sugar, beat until blended.
Add egg, orange and vanilla beat well.
Low speed, beat flour, salt until well blended. Wrap dough in plastic wrap and refrigerate for about 1 hour.
Heat oven 350
Line cookie sheet with parchment paper.
Shape dough into 1-inch balls and place on cookie sheet, 2 inches apart.
Press thumb into center of cookie to make indentation.
Bake 12 to 15 minutes until light golden brown.
Remake indentations with end wooden spoon, Remove from cookie sheet to rack cool completely. Fill each thumbprint with about 1/4 measuring teaspoon jam and sprinkle with powdered sugar.