In a stand mixer, cream butter with ¾ cup sugar. Add egg & vanilla & mix thoroughly.
Add flour, cream of tartar, salt & baking soda. Mix until incorporated.
In a separate small bowl, combine 2 Tbsp sugar with ¾ tsp cinnamon. Set aside.
Scoop some cookie batter, squish a Rolo in the center, pinch & smooth any seams by rolling the dough in your hands, hiding the rolo in the middle. Then roll cookie ball into cinnamon sugar mixture. (I use a #50 cookie scoop.) Place on a greased cookie sheet & repeat for all cookies.