Preheat your oven to 350°F (175°C) and grease an 8x8 inch baking pan.

In a medium bowl, whisk together flour, cocoa powder, baking powder, and salt until well blended.

In a large bowl, melt butter and stir in granulated and brown sugars until smooth. Add eggs one at a time, mixing well. Incorporate vegetable oil and vanilla extract.

Gradually add the dry ingredients to the wet ingredients, folding gently until just combined.

Fold in half of the chopped strawberries and crumbled shortcake biscuits into the brownie batter.

Pour the batter into the prepared pan, spreading evenly, and reserve remaining strawberries and shortcake for topping.

Bake for 25-30 minutes, checking for edges pulling away and a toothpick with moist crumbs.

Cool in the pan for 15-20 minutes, then cut into squares and serve warm.