For crust, in a large bowl, combine the flour, baking powder and salt. Add milk and 1/4 cup oil; mix well. Shape into a ball; knead 10 times.
On a lightly floured surface, roll into a 15x10-in. rectangle. Transfer to an ungreased 15x10x1-in. baking pan. Press onto the bottom and up the sides of pan. Prick with fork; brush with remaining oil. Bake at 425° for 12-14 minutes or until edges are lightly browned. Cool completely on a wire rack.
In a small bowl, combine the cottage cheese, ranch dressing mix, mayonnaise and milk; spread over crust. Sprinkle with cheese, broccoli, cauliflower, olives, celery, carrot, onion and pimientos.
For tombstones, in another small bowl, beat cream cheese and sour cream until fluffy. Place mixture in a resealable plastic bag; cut a small hole in a corner of bag. Pipe "RIP" onto crackers. Insert into pizza. Refrigerate until serving.