Preheat oven to 350 degrees F. Heat oil in medium dutch oven over medium heat. When hot, saute onions, carrots and celery, for 8-10 minutes or until softened. Add in peas, broccoli, and potatoes. Stir and cook for 5 minutes then add in the garlic; cook for 1 minute then add turkey breast. Reduce heat to low.
In a medium saucepan melt the butter over medium high heat; whisk in flour salt and pepper for one minute. Slowly whisk in chicken broth until thick and creamy, about 3 minutes. Once thickened, stir in cheddar cheese until melted. Pour sauce over turkey and vegetables.
Divide filling into 6 2 Cup ramekins for individual pies. Cut puff pastry into 6 rounds and place over ramekins. Bake for 25-30 minutes or until puff pastry is golden brown. You can also pour all filling into a 9×13 inch baking sheet and lay whole puff pastry sheet over top for casserole style. Bake time is the same.