In a medium sauté pan over medium heat, add in oil and poblano peppers. Cook for 10-15 minutes until softened and slightly charred. Sprinkle with salt. Set aside.
In bowl, mash avocado to desired consistency. Add in salt, lime juice cilantro and minced onion. Spread avocado over toasted sliced bread. Top with sautéed peppers and queso fresco.