Step 2) Combine flour, baking powder and salt; set aside in a small bowl. Combine 1 cup sugar and oil in a large bowl with electric mixer. Beat in eggs and vanilla. Gradually add flour mixture. Stir in mint chips.
Step 3) Press dough into 13 x 9-inch ungreased baking pan. Sprinkle with sugar. Bake for 20 to 25 minutes until bars are lightly browned around the edges but still soft in the center. Cool on wire rack. Cut into bars before serving.
*Substitute Variations – in place of mint chocolate chips, try the following.
Chocolate Peanut Butter Chip Cookies: 1 cup mini chocolate chips plus 1 cup peanut butter chips.
Chocolate Chip Toffee Cookies: 1 cup mini chocolate chips plus 2/3 cup toffee bits.