01 - Preheat oven to 400°F.
02 - Place sweet potatoes in a large pot, cover with water, and bring to a boil. Cook for 15-20 minutes until fork-tender. Drain well.
03 - Mash the sweet potatoes with olive oil, plant-based milk, salt, and pepper until smooth. Set aside.
04 - While potatoes cook, heat 2 tbsp olive oil in a large skillet over medium heat. Sauté onion, carrots, and celery for 5 minutes, until softened.
05 - Add garlic and bell pepper; cook for 2 minutes more.
06 - Stir in lentils, tomato paste, thyme, rosemary, smoked paprika, bay leaf, and vegetable broth. Bring to a simmer.
07 - Reduce heat, cover, and simmer for 25-30 minutes, stirring occasionally, until lentils are tender. Add more broth if needed.
08 - Remove bay leaf. Stir in soy sauce and frozen peas. Season with salt and pepper. Simmer uncovered for 5 minutes to thicken.
09 - Transfer lentil mixture to a large baking dish. Spread mashed sweet potatoes evenly on top.
10 - Use a fork to create ridges in the mash for a golden crust.
11 - Bake in the preheated oven for 20-25 minutes, until the top is slightly crispy and golden.
12 - Let rest 10 minutes before serving.