Heat a large skillet over medium heat. Add the butter and allow it to melt and coat the bottom of the pan, or heat the oil. Place the bread, cut side down, in the pan and let sit for about 2 minutes, until it is browned in spots. Remove from the pan and place on a cutting board or plate. Season both sides with salt and pepper
Spread the avocado dip on one or both halves of the bread. Layer on the chicken, bacon, and spinach, if using on the bottom half. Top the sandwiches with the rest of the rolls and serve.
Notes
You can use any cooked chicken you have around, from rotisserie chicken. For this sandwich, I like sliced breast meat, though you could use a thin cooked chicken cutlet or sliced thigh meat as well. And even though it’s not much of a recipe, if you don’t feel like making the avocado dip/spread, and you want to sub in sliced avocado, surely do that.