Unorthodox Shepherd's Pie

Why I Love This Recipe
I found this recipe in the back of Diane Mott Davidson's latest book, SWEET REVENGE. Great book about a lady caterer/sleuth. She includes all the recipes she uses in her story at the back of the book. I've tried this one and one for Gingerbread. Both delicious! Enjoy!
Ingredients You'll Need
2 lbs ground beef
2 Cups chopped onions
2 Cups chopped celery
2 Tbsp olive oil
1/4 Cup plus 1 tbsp all-purpose flour
2 Cups chicken stock
2 tsp dried thyme, crumbled
1/2 tsp dried rosemary, crumbled
1 tsp sea or kosher salt, or to taste
1/2 tsp freshly grated black pepper, or to taste
1 Cup frozen baby peas
1 Cup frozen baby corn
4 1/2 lbs russet potatoes
1 1/2 cups half-and-half
1 Cup grated Gruyere cheese
1/2 Cup freshly grated Parmesan cheese
additional sea salt, to taste
additional freshly ground black pepper
2 oz unsalted butter (1/2 stick), cut into bits
paprika
Directions
In a very large saute pan, saute the ground beef, onions, and celery in the oil over medium heat until the beef is browned and the vegetables are limp.
Add the flour and stir for 2 to 3 minutes, until the mixture begins to bubble.
Slowly add the chicken stock.
Stir until completely combined, then stir in the thyme, rosemary, and salt and pepper.
Cook and stir until the mixture is bubbling and thickened.
Stir in the peas and corn and set aside.
Bring a large quantity of salted water to boiling.
Peel the potatoes and drop them into the water.
Cook for about 40 to 45 minutes.
In a small saucepan, heat the half-and-half until it is steaming, but not boiling.
Preheat the oven to 350*F.
Butter two 9-inch deep-dish pie plates.
Grease or line a baking sheet.
Remove the potatoes from the heat, drain, and place them in the large bowl of an electric mixer.
Begin to beat the potatoes on low speed, slowly adding the hot half-and-half, the cheeses, and the additional salt and pepper.
Place half the beef mixture in each of the prepared pie plates.
Place half the potato mixture on top of the beef.
Scatter half the butter bits on top of each potato mixture.
Sprinkle generously with paprika.
Place the pies on the baking sheet and place them in the oven.
Bake for about 45 minutes, or until the potatoes are browned and the pies are completely heated through.
This goes well with a fruit salad.