Set oven to 400º. Slice the top of a garlic bulb off and place the peppers and garlic on a sheet pan. Drizzle with 1 tbsp olive oil over everything and roast for about 15 minutes. While they are baking, finely chop onions, basil, tomatoes.
Once the peppers and garlic are roasted, let them cool. Slice open the peppers and push seeds out, peel the skins off as best as you can discard. Squeeze the garlic out of the bulb. I use the entire bulb because I am crazy for garlic. You can use 4 cloves if you'd like to tone it down.
In a food processor, gently pulse the peppers, garlic, seasoning and remaining 1 tbsp olive oil together. Do not over process. You want the texture to be chunky. Add the mixture to a large bowl with diced tomatoes, diced onions and basil. Drizzle the balsamic vinegar or reduction over the mixture and with a spoon and fork, mix it together.
Thinly slice the baguette, spritz the baguette slices with oil or butter, place on a baking sheet (400º) for about 3-4 minutes *if you are making the bread cheesy, pull the baguettes out, add small bits of cheese on each baguette and place back in the oven for another 3-4 minutes.
Once the bread is crispy, cheese is melty, drizzle with the balsamic and serve right away.