When we roast tomatoes the aim is to evaporate the moisture slowly from it, by doing so we intensify the Umami-rich flavor of tomatoes, which gives a sweet, tangy flavor to any dish you add them to. Add them to a sandwich, salad, make a pesto or finely chop them and make a vinaigrette.
Preheat the oven at 100 C for 15 min, and mean time line up your baking tray with parchment paper. While the oven is being preheated, we will blanch the tomatoes to remove the skin. Fill a large bowl with cold water and ice for an ice bath. In a large pot heat the water at around 92 C. (Make sure the water is not at a boiling temperature, which ends up overcooking the tomatoes are ruining the firm texture that we are looking for when roasting them)
Using the tip of the paring knife, cut out the core of each of the tomatoes and score the bottom of the tomato with an X of each of them. Drop the tomatoes in the water and simmer them for a few seconds till the skin starts to pull away. The more ripe the tomatoes are the faster the skin will pull away
When done remove the tomatoes using a slotted spoon and transfer them in an ice bath to stop them from cooking. Remove them from the water bath as soon as they are cool and peel the skin off using a pairing knife
Cut the tomatoes lengthwise and then cut them again lengthwise into wedges. Remove the seeds and the core of the knife leaving behind only the flesh of the tomatoes. You can omit this step if you will be using the roasted tomatoes to make it into a sauce or soup
Now line up the tomatoes on the baking tray and season them with a pinch of thyme, basil, minced garlic, salt, and sugar to each one of them. Lastly, drizzle each one with olive oil and put the baking tray in the oven a let it cook for approximately 5 to 6 hours until the tomatoes are shrunk and most of the moisture are removed
Now you can use it immediately or can preserve once they are cooled down by transferring them into a container and top the tomatoes with olive oil to make sure they are submerged completely. It can be refrigerated for up to 10 days
Avoid using any cooking equipment that might react to the acidity of the Tomatoes. Make sure your baking tray is not made out of aluminum, to prevent leaching out of the metal and making food taste metallic