Preheat oven to 220°C. Oil oven trays; line with baking paper.
Place spinach in a fine sieve; squeeze excess water from spinach. Chop spinach coarsely; pat dry between sheets of absorbent paper.
Sprinkle half the spinach and half the combined cheeses over one pastry sheet. Top with another sheet of puff pastry; sprinkle with remaining spinach and combined cheeses. Cut pastry stack in half; place one stack on top of the other, press down firmly. Cut pastry crossways into 24 strips; twist strips, pinching ends to seal.
Place strips on trays. Bake about 15 minutes or until golden and crisp.