Preheat oven to 425°. Line a baking sheet with a silicone baking mat or parchment paper for easy clean up. Place fries in a single layer on the baking sheet. Bake 22-24 minutes.
While the fries are cooking, heat a large skillet over medium heat. Brown ground beef until fully cooked (no longer pink), breaking it up with a spatula while cooking.
Drain grease and return ground beef to skillet. Stir in 2 tsp of taco seasoning. Set aside.
Cut or tear American cheese slices into smaller pieces. Place in a microwave safe bowl with milk and jalapeño brine. Microwave in 30 second intervals and stir between intervals, until the cheese melts into a smooth sauce.
Remove fries from oven when they are a light golden color and toss with remaining 2 tsp of taco seasoning.
Assemble nacho fries and serve family-style on a large platter or set up a bar for everyone to assemble their own: fries, cheese sauce, cooked ground beef, and optional toppings.