Preheat your oven to 375°F (190°C). Prepare your baking sheet by lightly greasing it.

In a large bowl, combine flour, baking powder, salt, and black pepper. Whisk until blended. Add warm water and olive oil, stirring until a cohesive dough forms.

Turn the dough out onto a floured surface and knead for about 3-4 minutes until smooth and elastic.

Roll out the dough into a rectangle about 1/4 inch thick.

In a bowl, mix together mozzarella cheese, Parmesan cheese, cream cheese, mixed vegetables, parsley, and garlic powder until evenly distributed.

Spread the cheese and vegetable mixture evenly over the rolled-out dough.

Starting from one edge, roll the dough tightly into a log shape and cut into 8 equal pieces.

Place the cut rolls onto the prepared baking sheet. Brush the tops with melted butter.

Bake for 20-25 minutes until golden brown and bubbly.

Let cool for a few minutes before serving.