Mint Chocolate Chip Cookies

1 stick butter, softened
1 c. brown sugar, firmly packed
½ c. granulated sugar
½ c. vegetable oil
2 large eggs
2 tsp. pure vanilla extract
2 c. unbleached, all-purpose flour
½ c. unsweetened cocoa powder
4 oz. Andes Mint chips
4 oz. semi-sweet chocolate chips
½ tsp. Kosher salt
*Preheat oven to 350
* In large bowl, cream together butter and both sugars. In small bowl, [...]