01 - Preheat oven to 425°F. Arrange tater tots in a single layer on a large baking sheet and bake according to package directions, about 25 to 30 minutes, turning halfway through for even crispness.
02 - Bring a large pot of salted water to a boil. Cook elbow macaroni until al dente following package instructions. Drain and set aside.
03 - Melt butter in a medium saucepan over medium heat. Whisk in flour and cook for 1 minute. Gradually add whole milk and heavy cream, whisking constantly until smooth and slightly thickened, about 2 to 3 minutes.
04 - Reduce heat to low. Stir in shredded cheddar, Monterey Jack, smoked paprika, ground cumin, garlic powder, salt, and black pepper. Mix until cheese is fully melted and the sauce is smooth.
05 - Add drained macaroni to the cheese sauce and stir gently to coat the pasta evenly.
06 - Transfer baked tater tots to a large ovenproof dish. Spoon macaroni and cheese mixture evenly over the tater tots.
07 - Sprinkle shredded Mexican blend cheese on top. Return dish to the oven and bake for 5 minutes, or until cheese is melted and bubbling.
08 - Remove from oven and garnish with spring onions, diced tomato, jalapeño slices (if desired), and chopped fresh cilantro. Drizzle with sour cream and salsa just before serving.