Thaw bread dough according to package directions; let rise until doubled.
Meanwhile, in a large skillet over medium heat, cook the sausage until no longer pink; drain and transfer to a large bowl. Add the spinach, cheeses, oregano and garlic powder; set aside. Roll each portion of dough into a 14x12-in. rectangle. Spread sausage mixture lengthwise down the center of each rectangle. Gently press the filling down; dot with butter.
Bring edges of dough to the center over filling; pinch to seal. Place each loaf seam side down on a greased baking sheet. Tuck ends under and form into a snake shape.
Place an egg yolk in each of two small bowls; if desired, use red and yellow food coloring to tint one yolk orange and use green to tint the other. Brush stripes and diamond designs on snakes to decorate.
Bake at 350° for 25-30 minutes or until golden brown.
Cut out two small holes for eyes at one end of each loaf; gently press in olives. In each loaf, cut a slit below eyes; insert red pepper strip for tongue.