Brown your butter. Heat your butter over medium heat until it turns a golden yellow color. Pour butter in a heat proof bowl to cool. As the butter cools, it will get darker in color.
Combine flour, baking soda, and salt in a medium sized mixing bowl. Mix well and set aside.
Next add in white sugar and brown sugar to your butter. Mix to combine. Once well combined, add in your egg, vanilla extract, and tahini. Whisk together. Whisk until you get a light and creamy texture. This is the key to getting a crisp and chewy cookie.
Once the wet ingredients are well mixed, slowly add in the dry ingredients from step 3. Combine with a spatula until a soft dough forms.
Add in the chocolate chips and mix until they are well incorporated.
Let the dough rest at room temperature for 30 minutes.
Cover 2 baking sheets with parchment paper. Use a 1 tablespoon (0.5 oz) ice cream scoop to scoop cookie dough onto baking sheets. Cookies should be 2-3 inches apart.
Bake for 6 minutes until edges start to brown.
Let cookies cool for 10 minutes before putting them on a cooling rack.
Cool cookies for another 10 minutes before serving.
Notes
This recipe is for thin, chewy mini cookies. If you want a chunkier cookie, don't mix the batter as much. Mix only until just combined.