Preheat oven to 450ºF. Toss sweet potato with 1/2 of the olive oil, salt, and pepper. Spread out on a baking sheet in an even layer, and roast for 20 minutes, stirring occasionally.
Combine quinoa with water in a pot and bring to a boil. Cook according to package directions.
Once all of the water is absorbed into the quinoa, stir in lime juice, remaining olive oil, and garlic. Toss in cilantro and salt to taste. Then pour in drained and rinsed beans and about 3/4 cup roasted sweet potato. Stir to combine.
Heat up a small skillet, over medium heat, and pour in vegetable oil. Lay a tortilla in the skillet and spread on an even layer of cheese.
Cover half the tortilla with the quinoa and sweet potato mixture and top with spinach. Fold in half, flipping after 10 seconds to evenly brown both sides of the tortilla. Serve immediately.