Preheat oven to 400ºF.
Rough chop the tomatoes into large bite-size pieces and spread on parchment paper in an oven-safe dish.
If you do not have any roasted garlic, disperse the garlic cloves on top of the tomatoes. If you have roasted garlic, reserve it for later. Place in the oven and roast for 20-30 minutes or until color begins to appear.
Change oven to broil and continue roasting tomatoes to get a nice, scattered char (5-10 minutes). Keep a close eye on tomatoes during this process so they do not burn. Once you are happy with the char, remove the tomatoes from the oven and set the oven to 350ºF.
In a medium pot on medium heat add your olive oil and onions. Sauté the onions until they start to get a nice gold coloring (5-10 min), then turn them down to low, add your rosemary and thyme, and continue to caramelize the mixture until it is dark golden brown. This can take anywhere from 10-30 minutes depending on your heat, the natural sugars in the onion, and the size of your dice. Remember to stir often through this process.
Once golden brown, deglaze with red wine and reduce by half.
Rough chop the roasted garlic and add it to the pot with the charred tomatoes.
Adjust the heat to bring the mixture to a low simmer. Reduce to a stew-like consistency.
Finish with 1 oz of olive oil.
Season with salt and pepper, and adjust, if necessary, with red wine vinegar and brown sugar. Depending on the ripeness of your tomatoes, your flavor profile can vary from tart to sweet. You are looking for the ragout to have a very subtle sweetness.