Heat the olive oil over medium heat in a large saute pan and add the garlic. Cook for just a minute until it starts to color. Generously season the chicken on both sides with salt and pepper and add to the pan. Cook about 3 minutes per side until almost cooked through. Remove to a plate. Add the chorizo and break up. It will literally crumble into tiny bits. Cook for a minute or two and then add the onion to the pan. When the onion begins to caramelize add the mushrooms. When they are almost cooked thoroughly add the bell peppers. While everything is cooking together cut the chicken into bite sized pieces and add to the pan along with the olives. Deglaze the pan with the sherry vinegar and reduce heat to simmer and cook until the sherry vinegar has reduced. Season to taste with salt and pepper and add the cilantro.