Preheat the oven to 350 degrees F. Prepare two cookie sheets with parchment paper.
In a medium sized bowl, cream together butter, brown sugar, one egg and vanilla extract.
1 cup unsalted butter, ⅔ cup brown sugar, 1 large egg, 2 teaspoon pure vanilla extract
Add the flour and sea salt to the wet ingredients, mixing until just combined. The dough may seem firm and slightly dry, which is normal and ensures the cookies hold their shape during baking.
2 ⅔ cup all-purpose flour, ½ teaspoon sea salt
Roll the dough into small balls, about 2 teaspoons each, and place them on the prepared cookie sheets, about 12 cookies per sheet. (You can weigh each ball to be around 20 grams if desired.)
Make a small imprint in the centre of the cookies with your thumb, back of a ½ teaspoon or with the rounded end of a wooden spoon. Bake for 7-8 minutes.
While the last tray of cookies is in the oven, gently warm the pure pumpkin puree, then add the white chocolate chips and pumpkin pie spice and stir until fully melted.
⅓ cup pure pumpkin puree, ¾ cup white chocolate chips, ¼ teaspoon pumpkin pie spice
Once the cookies have cooled slightly, add a dollop of the white chocolate pumpkin filling to the centre indentation made in the thumbprint cookies. Top the cookies with a sprinkle of cinnamon if desired. Allow the ganache to cool and to set in the cookie.
This recipe yields approximately 36 small cookies. Enjoy!