Watch carefully. They only take about 5 minutes and can burn quickly.
You can add slices of tomato, onion, avocado...before or after cooking.
You will need tomato paste and a cheese of your choice. Salt, pepper, dried herbs, and red pepper flakes are optional. Assemble your pizzas and cook as above. If you take the pizzas out while the cheese is melted and the crackers are soft, you can cut them, cool them down and put them in a lunchbox. But we prefer them hot.
Ryvita with Satay Chicken
I often cheat by using some plain peanut butter with leftover spicy roast chicken. Simply spread your peanut butter or some satay sauce on the cracker. Add strips of cooked chicken. If you have time (which I usually don't) you can add a bit of something fresh and green like shredded lettuce, herbs, or green onion.
I am not including a proper recipe for satay sauce here. There are plenty on allrecipes.com. I sometimes make a quick one by placing half a cup of peanut butter, a spoon of a natural brown sugar, and a splash of rice wine vinegar in a pan. Melt carefully. Thin with water if necessary and whisk to a smooth sauce. Remove from the heat and add a splash of soy sauce. Whisk smooth again. Serve as above or with a fresh salad and cold roast chicken.