Cut the tomatoes in 1/2 lengthwise and toss evenly with olive oil, salt and pepper to get a nice even coating.
Spread tomatoes evenly on a sprayed sheet pan and put in a preheated 200 degree oven for about 1 11/2 hours. Check the tomatoes at this point to see if they are done. They should be shriveled and relatively firm. If they are still too wet, let them dry a little longer.
When the tomatoes are just about done, heat a little olive oil in a saute pan on the stove over medium heat. Saute the onions and garlic in the oil, stirring occasionally until they become translucent. Add in the wine and cook that down until it creates a glaze on the onions. Add in the cooked tomatoes and season if needed. Remove from the heat and fold in the basil.
Serve as a topping on a variety of products. such as our spring onion pancake or crostinis. You could even use it on an entree as a topper for something like polenta or a protein.
Notes
If you use larger tomatoes, you can slow roast them on a baking rack. You can do the same with the baby tomatoes if you have a fine enough rack that they won't fall through. This way, they dry out quicker in the oven. I like leaving them sitting in the oil, so they get a bit of a sauteed effect to them.Also, if you use larger tomatoes, they will need to be cut down to size after roasting.