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If you wish, you can use your oven instead of your stove to make tomato paste. This actually makes it easier because you don't have to stand over the stove while making it. You can actually leave the kitchen while the paste cooks.
Cook the tomatoes in a roasting pan at 350 degrees with the lid on, until the tomatoes break down. Then process into a puree and bake again, this time at 300 degrees with the lid off so that the water can evaporate and the puree can thicken.