I grew up eating traditional shepherd's pie, but sometimes I crave the same flavors in a quicker, easier version, and one that doesn't have to be baked in the oven. Wrapping the classic ingredients in a tortilla and making it all into a burrito is my fun twist. Also, it's great to make a bunch of burritos to freeze for later.
Heat 1 tablespoon oil in a large nonstick over medium-high heat. Add the beef and cook, breaking up chunks, until no longer pink, 3 to 5 minutes. Remove the beef from the skillet and set aside.
In the same skillet, combine the onion, carrots and garlic. Continue to cook over medium-high heat until the onions soften, 2 to 3 minutes. Return the beef to the skillet. Stir the gravy granules and warm water together in a cup and add it to the skillet. Simmer until most of the liquid has evaporated. Stir in the peas and thyme.
Heat the mashed potatoes in the microwave or in a small saucepan until warmed through.
Lay a tortilla on a cutting board and spread 1/2 cup mashed potato over the bottom third of the tortilla. Top with a quarter of the beef mixture. Fold the bottom edge of the tortilla over the filling, then bring in the sides and roll until the filling is enclosed. Set aside, placing it on the crease-side down so it doesn't open up. Repeat with remaining tortillas and fillings.
Heat the remaining 1 tablespoon oil over medium heat in a large nonstick skillet. Place 2 burritos, crease-side down, in the skillet (this will help seal close the burrito) and sear until golden brown, about 1 minute per side. Transfer to a cutting board and repeat with the remaining burritos.
Slice the burritos in half on an angle with a serrated knife and enjoy.