Browned Butter Crinkle Cookies with Salted Caramel Frosting

INGREDIENTS

1 cup

salted butter (, diced into cubes)

2 1/4 cups

all-purpose flour

2 tsp

cornstarch

1 tsp

baking powder

1/4 tsp

baking soda

1/4 tsp

salt

1/2 cup

granulated sugar

1/2 cup

packed light-brown sugar

large egg

large egg yolk

2 tsp

vanilla extract

1/4 cup

granulated sugar (, for rolling cookies)

1/4 cup

+ 2 Tbsp caramel sauce or caramel ice cream topping ((I used Hershey's))

1/4 cup

butter (, softened)

1/2 tsp

vanilla extract

2 cups

powdered sugar

3/4 tsp

coarse sea salt (, divided)