In a small saucepan, brown 2 Tbsp of the butter and let cool completely.
Heat oven to 350F. Line two baking sheets with parchment paper or silpat.
In a medium bowl, sift the flour, baking soda and salt together.
In another large bowl, using an electric mixer at medium speed, beat together the butter, cooled brown butter and sugars until smooth and mixed together well.
Add the egg and vanilla and mix on low speed until mixed in.
Fold in the flour mixture and mix in until just incorporated.
Add dates and nuts until just incorporated.
Chill dough if dough is warm and bake!
Small cookies bake 8-10 minutes
Large cookies bake 10-13 minutes.