Preheat the oven to 425°F (220°C). Line a baking sheet with parchment paper.
Wash and peel the russet potatoes. Cut them into thin fry shapes, about ¼ inch wide.
In a large bowl, toss the cut fries with olive oil, garlic powder, paprika, cumin, chili powder, salt, and black pepper until well coated.
Spread the seasoned fries out evenly on the prepared baking sheet in a single layer.
Bake in the preheated oven for 25-30 minutes, flipping halfway through until golden brown and crispy.
While the fries are baking, prepare the cheese sauce. In a saucepan over medium heat, whisk together the milk and flour until smooth.
Gradually stir in the shredded cheddar cheese until fully melted and the sauce is creamy. If desired, add hot sauce for extra spice.
Check the fries; once done, remove them from the oven and let them cool slightly.
Arrange the fries on a serving platter and drizzle the cheese sauce generously over the top.
Serve with a side of sour cream and salsa for dipping.