Caramelized Onion and Garlic Pasta without crumbs

2 tablespoons olive oil for cooking the onions 2 large red onions peeled, halved and thinly sliced 1/2 teaspoon thyme leaves optional * 1 tablespoon balsamic[...]

1 large whole head of garlic 1 1/2 tablespoons olive oil 9 cups thinly sliced sweet onions 2 1/2 cups sliced leeks 1 teaspoon salt 1 teaspoon dried thyme 2[...]