Preheat oven to 350 degrees F.
Cover an 8-inch or 9-inch square pan with tin foil so that it hangs over the edges, and lightly grease the foil.
Blend ½ cup vegetable oil or melted butter, 1 cup granulated sugar, and 1 teaspoon vanilla in large bowl.
Add 2 large eggs; mix well with spoon.
Combine ½ cup all-purpose flour, ⅓ cup Hershey's Cocoa, ¼ teaspoon baking powder, and ¼ teaspoon salt in a medium bowl.
Add flour mixture to eggs and stir just until well blended.
Spread batter in prepared pan.
Bake for 20-25 minutes or just until brownie begins to pull away from edges.
Cool in pan for about 10 minutes, then gently lift the foil out and allow brownies to cool before cutting.
