Preheat oven to 325°F and spray a 9x13-inch baking pan with baking spray. Line pan with parchment paper, leaving a few inches of overhang so you’ll be able to easily lift the bars from the pan after baking and cut into bars.
In the bowl of a stand mixer, beat browned butter on medium speed until smooth and creamy. Add both sugars and vanilla. Mix until fluffy. Add eggs and mix well.
Add flour, baking soda, and salt. Mix on low speed until mostly combined, then medium speed until completely combined. Stir in chocolate chips and 1 (10-oz) package of mini chocolate eggs.
Press dough into the prepared pan. (The dough is a little sticky, so it might be helpful to spray a rubber spatula with nonstick spray and use it to spread the dough.)
Bake for 12 minutes. Remove from oven and sprinkle top of dough with half of the second bag of mini chocolate eggs. Return to oven and bake for 12 to 15 minutes more, or until cookie is golden brown and set in the center.
Remove from oven and let cookie cool slightly. Lift cookie from the pan and cut into bars.
Serve and enjoy!