01 -
Turn your oven to 350°F (175°C). Put parchment paper in a 9x13 inch pan with extra hanging over the sides for easy lifting later, or just coat with cooking spray.
02 -
Stir together 2 tablespoons sugar and 2 teaspoons cinnamon in a small dish. Put it aside for now.
03 -
Mix the soft butter with 2 cups sugar in a big bowl until it's fluffy and pale, roughly 2-3 minutes.
04 -
Add eggs one by one, then mix in the vanilla.
05 -
In another bowl, stir together flour, cream of tartar, baking soda, and salt.
06 -
Slowly add your dry mix to your butter mix, stirring just enough to combine. You'll end up with thick dough.
07 -
Dump the dough in your pan and spread it flat. Since it's sticky, try using wet hands or a flat tool to make this easier.
08 -
Dust the cinnamon-sugar mix all over the top of your dough.
09 -
Stick in the hot oven for about 25-30 minutes. It's done when the edges turn light gold and a toothpick stuck in the middle comes out mostly clean. Don't cook too long if you want them soft.
10 -
Let the whole thing cool down completely on a wire rack before cutting into squares.