Preheat oven to 350°F.
In the bowl of an electric mixer fitted with the paddle attachment, but the butter on medium speed until creamy, about 3 minutes. Add the brown sugar and beat on medium speed until mixture is light and fluffy, about 4 minutes.
Add vanilla, egg yolk, egg and a tablespoon of warm water on low speed and continue to mix until combined.
In a medium bowl, whisk together the flour, baking soda, and salt. With the mixer on low speed slowly add the flour mixture to the bowl. Add the chocolates, crushed pretzels, and toffee bits and mix until combined.
Divide the cookie dough into 24 rounded scoops and divide them among 3 sheet pans lined with parchment paper placing them about 2 inches apart. Freeze the dough on the sheet pans 20 minutes.
If you are going to freeze the dough for later baking, put them in the freezer for 12 hours, and then place them in a zip top bag and freeze until you are ready to bake them. (See note below.)
Remove the sheet pans from the freezer and sprinkle with sea salt. Bake in the oven for 10 minutes, or until the edges of the cookies are golden brown and the center is set.