Cut the chicken breast into bite-sized pieces.
Slice the cherry tomatoes and onion into bite-sized pieces.
Add olive oil to a pan and cook the chicken breast.
Add the onion and stir-fry.
Add the tomatoes, salt, and pepper, and stir-fry.
Place the Greek yogurt and cooked ingredients in a bowl.
Top with mozzarella cheese and bake in the oven for 5 minutes.