Begin by heating the olive oil in a large skillet over medium heat. Sauté the diced sweet onion for about 5 minutes, allowing it to soften and sweeten.

While the onion cooks, use a medium bowl to mash the drained black beans with a fork; this creates a creamy base for your filling.

Once the onion is fragrant and translucent, add in the minced garlic and shredded chicken. Stir for a few minutes to meld the flavors together.

Incorporate the mashed beans and taco seasoning, mixing thoroughly, then cook for an additional 3 minutes. Finally, add the Greek yogurt and minced cilantro, stirring to blend the ingredients well before removing from heat.

In a separate pan, heat up the tortillas one by one until they reach a light golden color, roughly 1-2 minutes per side. This ensures a crispy texture that elevates your taco experience.

To assemble, sprinkle some shredded cheese on your tortilla, followed by two generous spoonfuls of the chicken and bean mixture. Top with your choice of sliced tomatoes and jalapenos if desired.

Carefully fold the tortilla over and place it on a plate. Repeat until all tortillas and filling are used. Garnish with thinly sliced lettuce if you like.