No No..you just have to bake it. Just preheat the oven to 200 degrees. Wash and cut the tomatoes. Gently squeeze out the seeds. Place the tomatoes on a non-stick cookie sheet, and sprinkle with salt to taste.Bake until tomatoes take on a leathery texture. This process can take a day, smaller pieces will require less oven time.
U get canned ones n u can make them at home as well. Peel the tomatoes by putting them in boiling water for few minutes and then transfer to ice water. This step is optional..u can make however u prefer..with skin, or without skin. Cut into quarters and take out the seeds. Lay on a tray, sprinkle salt and herbs whichever way u like. See that they dont touch each other..and keep in the sun to dry..this will take few days..or can b done in oven as well on lowest temperature..but itll take many hours. They shouldnt dry completely..should be slightly soft to touch not brittle. Then store in ziplock in freezer and use whenever u want.