In a large bowl, mix together together flour, cake mix, and baking soda. Set aside.
In a stand mixer bowl, cream together the butter, shortening, and sugars on medium speed. Add the egg and vanilla, and beat until creamy.
Add the flour mixture to the wet ingredients and mix until just combined. Do not OVERMIX the dough.
Preheat oven to 350 degrees.
Scoop by rounded tablespoons of the cold dough onto a a parchment or silicon lined baking sheet. Shape your cookie dough balls to be “taller” than they are wide. Bake for 10-12 minutes until edges are obviously done. The centers will still appear very soft, but the cookies will set as they cool.
Allow the cookies to cool on the baking sheet for a few minutes and transfer to a wire rack to cool completely.
Microwave the caramels and water together for 1 minute (addition time if needed). Drizzle over top of the cookies and sprinkle with sea salt.