For the salsa, add all ingredients to a food blender and pulse until well mixed. Avoid pulsing for too long as the mixture can become very runny.
Refrigerate for at least an hour before serving.
Into a bowl, add the chicken breasts, crushed garlic cloves, chilli powder, cumin, oregano and paprika.
Rub the spices into the chicken until well coated.
Into a slow-cooker, add the chopped tomatoes, peppers, onion and mushrooms along with the coated chicken breasts.
Combine together and place on a low heat for 6 hours, stirring occasionally.
Once cooked, using two forks shred the chicken in the mix before topping with fresh coriander.
Serve with tortilla wraps, lettuce and salsa.
For a vegetarian option, swap out the chicken for meat-free substitutes, more vegetables (broccoli and cauliflower work great) or tofu!