Heat frying pan on low - medium heat with olive oil. Add red onions evenly dispersed in the pan. Let them cook slowly, stirring occasionally, for about 35-40 minutes. When onions are brown and a bit sticky drizzle with balsamic vinegar and cook for about another minute. Remove from pan and set aside.
Preheat oven to tart shell box instructions. On a baking sheet, lay out tart shells. Add a generous dollop of Habibi’s Sweet Onion Hummus into shell. Top each with a few onions from balsamic onion mixture. Bake for about 10 minutes, or until tart edges look slightly golden. Remove, let cool slightly and garnish with fresh thyme.