Preparation is key to a smooth cooking experience. Start by preheating your oven to 350°F (175°C).
While the oven is heating, you can begin preparing your ingredients.
If you haven't already cooked your chicken, now is the time to do it.
Shred or dice the chicken into bite-sized pieces once it's cooled enough to handle.
Heat the olive oil in a large skillet over medium heat. Add the diced onion and cook until it becomes translucent, about 3-4 minutes.
Then, stir in the frozen peas and carrots (or your choice of mixed vegetables) and cook until they are slightly softened, about 5 minutes.
This step helps to remove excess starch and prevents the casserole from becoming too gummy.