Preheat the oven properly – Set your oven to 350°F (175°C) and line baking sheets with parchment paper.

Cream butter and sugar – Beat softened butter and granulated sugar until light and fluffy. This step creates air pockets for soft texture.

Add eggs and vanilla – Mix in eggs one at a time, then add vanilla extract. Beat until smooth and well combined.

Combine dry ingredients separately – In another bowl, whisk flour, cream of tartar, baking soda, and salt to ensure even distribution.

Bring dough together gently – Gradually add the dry ingredients to the wet mixture. Mix just until combined. Avoid overmixing to keep cookies tender.

Prepare cinnamon sugar mixture – In a small bowl, combine sugar and cinnamon for coating.

Shape and coat dough balls – Scoop tablespoon-sized portions of dough and roll into smooth balls. Roll each ball in the cinnamon-sugar mixture until fully coated.

Place on baking sheet – Arrange dough balls about 2 inches apart to allow spreading.

Bake until lightly golden – Bake for 10–12 minutes until edges are set and tops are crackled. Centers should still look slightly soft.

Cool before serving – Let cookies rest on the baking sheet for 5 minutes before transferring to a cooling rack.