Pre-heat your oven to 400 degrees.
If you are making homemade mashed potatoes, start those first then move along to the shepherd's pie. Click here to see my recipe for garlic cream cheese mashed potatoes.
Heat a 12" oven-safe pan over medium high heat and add the olive oil, meat, onion, garlic, thyme, salt, and pepper to the pan and cook until the meat is browned.
Add in the peas and carrots and stir to combine.
Sprinkle the corn starch over the meat/veggie mixture and then stir until you see no more white. Then add in the beef broth and cook until it starts to bubble. (Just about 2 minutes)
Top with the mashed potatoes. If you are using refrigerated or instant, just make sure to warm them first according to the package directions.
Top the mashed potatoes with the parmesan cheese and place in the oven for 30 minutes.
If you'd like the top to be browned more after the 30 minutes, just set the oven to broil and watch very carefully for just a couple of minutes.
Let the shepherd's pie rest for 10 minutes before serving then enjoy!