Preheat your oven to 350°F (175°C).
In a large mixing bowl, combine the room temperature unsalted butter, brown sugar, and granulated sugar. Use an electric mixer to beat them together until light and fluffy, about 2-3 minutes.
Crack in the two large eggs, one at a time, mixing well after each addition. Then, pour in the vanilla extract and mix until everything is combined.
In a separate bowl, whisk together the all-purpose flour, cornstarch, baking soda, and salt.
Gradually add the dry mixture into the wet ingredients, mixing on low speed until just combined.
Using a spatula, gently fold in the broken mini pretzels and frozen Nutella chips until evenly distributed.
Using a cookie scoop or tablespoon, drop rounded balls of dough onto the prepared baking sheets, spacing them about 2 inches apart.
Lightly sprinkle a pinch of sea salt on top of each cookie dough ball.
Place the baking sheets in the preheated oven and bake for 10-12 minutes, or until the edges are golden brown.
Let the cookies cool on the sheets for about 5 minutes before transferring them to a cooling rack to cool completely.
