Preheat oven to 425 F . Line rimmed baking tray with parchment paper and set aside.

In medium bowl, toss together sweet potato pieces, 1 tsp grapeseed oil, 1 tsp cumin, and oregano. Spread mixture out in a single layer on prepared baking tray and roast, stirring once or twice during roasting time, until potatoes are fork tender and lightly caramelized, about 25 to 35 minutes.

Meanwhile, in small saucepan, warm remaining 1 Tbsp grapeseed oil over medium heat. Once hot, add onion and sauté until tender, about 4 minutes. Add garlic and continue to cook until both onions and garlic are starting to lightly caramelize. Stir in lentils, salt, paprika, remaining 1 tsp ground cumin, maple syrup, tomato paste, and water. Stirring, bring mixture to a simmer. Cover, reduce heat to low, and let mixture simmer gently, stirring occasionally, for 10 minutes. If mixture gets too dry, add a bit more water. Remove from heat, stir in lime juice, and adjust seasoning, as desired, with additional spices or lime juice. Set aside.

Lay tortillas out in single layer on baking tray and toast in oven for 4 minutes. Flip and continue to toast until tortillas are crispy, about another 4 to 8 minutes.

Over each tortilla, evenly spread a layer of refried lentils and then top with roasted sweet potato, avocado, diced tomato, cheese or nutritional yeast, and a sprinkle of pumpkin seeds. Serve immediately.