Prepare the "Beef" Filling: Heat the olive oil in a large skillet over medium heat. Add the diced onion, celery, and carrots, and cook for 5-7 minutes until the vegetables are softened. Add the garlic and cook for an additional 1-2 minutes.

Add Vegetarian Crumbles and Vegetables: Stir in the water, vegetarian beef crumbles, corn, and peas. Mix in the tomato paste, salt, and pepper, and cook for another 5 minutes, stirring occasionally, until everything is well combined and heated through.

Make the Gravy: This Vegetarian Shepherd’s Skillet Pie is a warm and hearty meal that’s perfect for any night of the week. Packed with vegetables and topped with creamy mashed potatoes, it’s a satisfying, meatless twist on a comforting classic. Enjoy it with a side salad or steamed greens for a complete meal! Cook for 2-3 minutes until the flour is golden brown. Gradually add the vegetable stock, stirring continuously to prevent lumps. Add the rosemary, thyme, and soy sauce, and continue to cook until the gravy thickens, about 5 minutes.

Combine Filling and Gravy: Pour the gravy over the "beef" and vegetable mixture in the skillet, stirring to combine. Reduce heat to low and let simmer while preparing the mashed potato topping.

Prepare the Mashed Potato Topping: Drain the boiled potatoes and mash until smooth. Stir in the milk, butter, salt, and pepper until the potatoes are creamy and well-seasoned.

Assemble the Skillet Pie: Spread the mashed potatoes evenly over the "beef" and vegetable mixture in the skillet, creating a smooth layer on top. Use a fork to create a decorative pattern, if desired.

Bake: Preheat the oven to 400°F (200°C). Transfer the skillet to the oven and bake for 20-25 minutes, or until the mashed potatoes are golden and the filling is bubbly around the edges.

Serve: Remove from the oven, let cool slightly, and serve hot. Enjoy this comforting, vegetarian twist on a classic shepherd's pie!