Lemon Thumbprint Cookies With White Chocolate Ganache

For the ganache:
You'll want to prepare ganache and let it sit in the fridge prior to starting the cookies. Then it will be ready when your cookies are cooled.
Place chopped chocolate into a heatproof bowl. Bring heavy cream to a boil in a saucepan over medium heat. Pour the hot cream over the chopped white chocolate and stir until completely melted. Cover the bowl and set it in the fridge to thicken.
Meanwhile, preheat oven to 350 F. In a bowl beat butter, sugar, zest, lemon juice, vanilla and salt until light and creamy. Add in the egg and continue beating. Slowly add in flour until completely blended.
Using a small cookie scoop, scoop out a small amount of dough and roll it gently into a ball shape. Place on a lightly greased or lined cookie sheet about two inches apart. Using the back end of a 1/4 teaspoon, gently make an indentation into the cookie. Repeat with the remaining dough.
Bake cookies for 12-14 minutes. Remove from oven and let them stand for 5 minutes before placing on a cooling rack to cool completely.
When cookies are cool, fill each cookie cavity with a teaspoon of white chocolate ganache.
For a little more lemon flavor, zest another lemon into a bowl. Add a tablespoon of sugar and stir until everything is well combined. Sprinkle zest over cookies.
Cookies adapted from King Arthur Flour Company.
Makes 3 1/2 dozen small cookies