Preheat the oven to 350ºF. Line a loaf pan with parchment paper.
In a skillet, heat oil at medium-high heat. Add onions and sauté until translucent. Add garlic and cook for 30 seconds. Transfer to a large bowl and allow to cool slightly.
In the same bowl, add the ground meat, breadcrumbs, egg, 1/4 cup of the guava bbq sauce (save the rest for glazed the top of the meatloaf), Worcestershire sauce, salt, and pepper. Mix all together until combined. Careful not to over mix or the meat may turn out too tough/dense.
Transfer the meatloaf mixture to the prepared loaf pan and form into a loaf. Brush remaining guava bbq sauce on top of the loaf.
Bake for 60-65 minutes or until fully cooked. The internal temperature should be 165ºF. Remove from oven and allow to cool for 10 minutes. Serve and enjoy!