This is really more of a technique than a recipe. Use a meaty variety of tomatoes, like Roma, Early Girl, or Costoluto. Sometimes you’ll see these labeled as “paste” tomatoes at the farmers’ market. Adjust the amount of olive oil depending on the size of your baking dish. The number of garlic cloves is just a suggestion--add as many as you like. Measure those with your heart, as they say. This makes about 1 quart, for which you can charge $45 if you're feeling salty.
Halve the tomatoes. Arrange them, cut side up, in a snug single layer in baking dish just large enough to hold them. Tuck the garlic cloves between the tomatoes. Drizzle with a lot of olive oil. How much? Depends on size of your pan and how many tomatoes you’ve got, but you want them resting in a generous puddle of oil. Sprinkle generously with sea salt and freshly ground black pepper.
Bake for 1 hour or until the tomatoes and garlic are very tender. Cool, and transfer to a quart-size jar, along with any oil and juices in the baking dish. Refrigerate for 2 weeks or freeze for 2 months.