Cherry, grape or small Roma tomatoes
Whole gloves of garlic, unpeeled
Olive oil
Herbs such as fennel, thyme, or rosemary
Preheat oven to 225°F. Halve each cherry or grape tomato crosswise, or Roma tomato lengthwise and arrange on a parchment-lined or sprayed baking sheet along with the cloves of garlic. Drizzle with olive oil, just enough to make the tomatoes glisten. Sprinkle herbs on and salt and pepper.
Bake the tomatoes in the oven for about 4-6 hours. You want the tomatoes to be shriveled and dry, but with a little juice left inside–this could take more or less time depending on the size of your tomatoes.
Either use them right away or let them cool, cover them with some extra olive oil and keep them in the fridge.