Brother's Birthday Brownies

I'm making these this weekend for my brother's birthday dinner Sunday at Mom and Dad's. Chocolate Mint is his favorite (very much not mine :) )

MINT CHOCOLATE CHIP BROWNIES
3/4 c. cocoa
1/2 tsp. baking soda
2/3 c. butter, melted & divided
1/2 c. boiling water
2 c. sugar
2 eggs
1 1/3 c. flour
1 tsp. vanilla
1/4 tsp. salt
1 3/4 c. (10 oz. pkg.) mint chocolate chips

Heat oven to 350 degrees. Grease a 9 x 13 inch pan. In large mixing bowl, combine cocoa and baking soda. Blend in 1/3 cup melted butter. Add boiling water; stir until mixture thickens. Stir in sugar, eggs and remaining 1/3 cup melted butter; stir until smooth. Add flour, vanilla and salt; blend completely. Stir in mint chocolate chips.
Pour into prepared pan. Bake 35 to 40 minutes or until brownies begin to pull away from sides of pan. Cool completely in pan. Cut into squares. About 36 brownies.