½cupsalted buttersoftened but not melted (1 stick)
⅓cuplight brown sugarpacked
1largeeggseparated
½teaspoonvanilla extract
1cupBob's Red Mill Unbleached White All Purpose Flour
½teaspoonKosher salt
1 ¼teaspoonground cinnamondivided
¼teaspoonground nutmeg
1 ¼cupfinely chopped walnuts or pecansoptional
1cupApple butter
Instructions
Preheat the oven to 350 degrees and line a baking sheet with a Silpat or parchment paper.
Mix butter, sugar egg yolk and vanilla until well combined.
Stir into flour, salt, ½ teaspoon cinnamon and nutmeg until just combined.
Roll into 1 inch balls.
In a small bowl, combine chopped nuts and remaining cinnamon.
Roll each ball in egg white and then the nuts mixture.
Place each ball onto the baking sheet around an inch apart.
Using your thumb or the back of a spoon, create a small hole in the middle of each cookie being careful not to go all the way through (the "thumbprint").
Bake 10-12 minutes. Cool completely.
Fill the thumbprints with apple butter. Serve immediately.
Notes
If you don't want to use the nuts/cinnamon mixture you could substitute it by rolling the balls in a mixture of 2 Tablespoons of sugar + 1 teaspoon cinnamon.
These will last up to 4 days covered at room temperature.