In a large mixing bowl, beat together the Duck Fat, butter, brown sugar, and granulated sugar until creamy and light (about 2-3 minutes).
Mix in the eggs one at a time, then stir in vanilla until fully combined.
In a separate bowl, whisk together flour, baking soda, and salt. Gradually add to the wet ingredients, mixing just until combined.
Stir in the chocolate chips or chunks. Cover the dough and chill for at least 1 hour (overnight is even better).
Scoop dough into 2-tablespoon mounds and place on a parchment-lined baking sheet, spaced 2 inches apart. Bake for 10-12 minutes, or until edges are golden and centers are just set.
Let cool on the baking sheet for 5 minutes, then transfer to a rack.
Recipe Note
Don’t be surprised when everyone asks what your secret ingredient is. Duck fat gives these cookies their rich, unforgettable flavor!