Preheat oven to 350 degrees F. Line a baking sheet with parchment paper. Set aside.

In a small bowl, combine 1/4 cup granulated sugar and a pinch of kosher salt. Set aside.

In a large mixing bowl, beat butter, vegetable oil, 1 1/4 cup granulated sugar, powdered sugar, water, and eggs until combined. Slowly add in flour, baking soda, cream of tartar, and salt. Mix until blended.

Dough may be slightly crumbly, but not sticky. Using a 2 Tbsp cookie scoop, spoon a dough ball and roll it in your hands. Then roll dough ball in sugar and salt bowl. Place on cookie sheet.

Using a glass with a flat bottom, dip glass in sugar bowl, then press on top of cookie. Flatten cookie so that the dough spills out over the sides of the glass to create a lip (for the icing). Repeat for all dough balls.

Bake cookies for 8-10 minutes. Remove and cool completely on wire rack.

For the icing, beat together the butter and sour cream for 3 minutes. Add in powdered sugar and food coloring, beating until well blended. Add up to 2 Tbsp milk, if needed to create an icing that is thick, but not runny or TOO thick.

Spread icing over cooled cookies. ENJOY.