Preheat the oven to 350°F. In a small saute pan over medium-low heat, saute the red onion in the olive oil with the salt until slightly browned, stirring occasionally, about 8-10 minutes.
Toss the shredded chicken in the bbq sauce in a small bowl, set aside.
Place the English muffins on a baking sheet, cut side up. Top the muffins with the bbq chicken, onions, and cheese. Bake for 5-8 minutes until heated through and the cheese is melted. Top with the cilantro.