Step 1Preheat the oven to 150 °C/ 300 °F (fan assisted), or 170 °C/ 340 °F (conventional). Start by whipping the egg whites. with cream of tartar (or use 1/8 tsp of apple cider vinegar). Optionally, add 1/8 to 1/4 tsp popcorn extract and/or any spices and herbs of choice.