Combine BelGioioso Mascarpone, thyme, rosemary, oregano, Italian parsley, salt and black pepper in large bowl to make the herb Mascarpone. Refrigerate until ready to use.
For the balsamic onion confit, place sliced red onions in a medium sauté pan. Add vinegar and cook over medium high heat. Stir often and cook until onions are tender and the balsamic vinegar has reduced by half. Let cool. To assemble, spread herb Mascarpone on each crostini and top with balsamic onion confit.