Kitchen Sink Brownie Cookies

1/4 cup butter, at room temperature
1/4 cup vegetable shortening
1/4 cup granulated sugar
1 egg
1 egg yolk
1 (17.6 ounce) box brownie mix with milk chocolate chunks
2 tablespoons unsweetened cocoa powder
1/2 cup salted mixed nuts
1/4 cup miniature M&Ms
1/4 cup white chocolate chips

Heat oven to 325 degrees F. Coat 2 baking sheets with cooking spray.

At medium-high speed, beat butter and shortening until smooth. Beat in sugar until fluffy. Beat in egg and yolk until combined. Add brownie mix and cocoa powder; beat until combined. Stir in nuts, M&Ms and white chocolate chips.

Drop batter by 1/4 cupsful onto baking sheets 3 inches apart. Bake for 16 minutes, until edges are set. Cool for 5 minutes. Remove from pan; cool completely on racks.