• In the bowl of your electric mixer, beat the butter and sugars until combined. Stop mixer and scrape sides, combine again.
• Beat in eggs and vanilla. Stop the mixer and scrape sides, combine again. In another large bowl, whisk together flour, baking soda, and cream of tartar.
• In two additions, add flour mixture to the butter mixture, beating until just combined. Do not overmix. Chill dough for at least one hour before baking.
• Line baking sheets with parchment paper or silicone baking mat.
• Using a spring-release scoop drop onto a silicone mat on a sheet pan. (My spring release scoop holds 1 tablespoon of dough.) Press dough slightly flat with your palm or the bottom of a glass.
• Bake at 350 for 11 to 13 minutes, or until edges and bottoms are very lightly browned.
• Cool for 2 minutes on the sheet pan before moving to a wire rack to cool completely.
• These are good for 5 days stored in an airtight container on the counter before they start drying out. If you frost with cream cheese frosting, you'll need to store them in the refrigerator.
• This cookie dough freezes great!

FROSTING

• Beat the butter and cream cheese until smooth.
• Add 1 cup of the sifted powdered sugar, whipping cream, and extract and mix until creamy.
• Slowly add the remaining powdered sugar and mix until smooth.
• Frost cookies and serve. Store in an airtight container in the refrigerator.